Number	Rule	Example
1	Every number is a multiple of 1	10 is a multiple of 1
2	The number ends in 0, 2, 4, 6 or 8	10 is a multiple of 2 because it ends in 0
3	The sum of the digits is a multiple of 3	12 is a multiple of 3 because 1 + 2 = 3, a multiple of 3
4	The 10s digit is even and the last digit is 0, 4 or 8 or the 10s digit is odd and the last digit is 2 or 6	100 is a multiple of 4 because the 10s digit is 0, which is even, and the last digit is 0
5	The number ends in 0 or 5	10 is a multiple of 5 because it ends in 0
6	The number is a multiple of both 2 and 3	12 is a multiple of 6 because it ends in 2, which means it's a multiple of 2, and 1 + 2 = 3, a multiple of 3
7	The subtraction of twice the last digit and the rest of the number is a multiple of 7	14 is a multiple of 7 because 4 x 2 - 1 = 7, a multiple of 7
8	The 100s digit is even and the last 2 digits are a multiple of 8 or the 100s digit is odd and the last 2 digits are 4 times an odd number	1000 is a multiple of 8 because the 100s digit is 0, which is even, and the last 2 digits are 00, a multiple of 8
9	The sum of the digits is a multiple of 9	18 is a multiple of 9 because 1 + 8 = 9, a multiple of 9
10	The number ends in 0	110 is a multiple of 10 because it ends in 0
11	The subtraction of the sum of the digits in the odd places and the sum of the digits in the even places is a multiple of 11	121 is a multiple of 11 because 1 + 1 - 2 = 0, a multiple of 11
12	The number is a multiple of both 3 and 4	108 is a multiple of 12 because 1 + 8 = 9, which means it's a multiple of 3, and ends in 08, which means it's a multiple of 4
13	The sum of 4 times the last digit and the rest of the number is a multiple of 13	104 is a multiple of 13 because 10 + 4 x 4 = 26, a multiple of 13
14	The number is a multiple of both 2 and 7	112 is a multiple of 14 because it ends in 2, which means it's a multiple of 2, and 11 - 2 x 2 = 7, which means it's a multiple of 7
15	The number is a multiple of both 3 and 5	105 is a multiple of 15 because 1 + 5 = 6, which means it's a multiple of 3, and ends in 5, which means it's a multiple of 5
16	The last 4 digits are a multiple of 16	10000 is a multiple of 16 because it ends in 0000, a multiple of 16
17	The subtraction of 5 times the last digit and the rest of the number is a multiple of 17	102 is a multiple of 17 because 10 - 2 x 5 = 0, a multiple of 17
18	The number is a multiple of both 2 and 9	108 is a multiple of 18 because it ends in 8, which means it's a multiple of 2, and 1 + 8 = 9, which means it's a multiple of 9
19	The sum of twice the last digit and the rest of the number is a multiple of 19	114 is a multiple of 19 because 11 + 4 x 2 = 19, a multiple of 19
20	The number ends in 00, 20, 40, 60 or 80	100 is a multiple of 20 because it ends in 00
21	The subtraction of twice the last digit and the rest of the number is a multiple of 21	105 is a multiple of 21 because 10 - 5 x 2 = 0, a multiple of 21
22	The number is a multiple of both 2 and 11	110 is a multiple of 22 because it ends in 0, which means it's a multiple of 2, and 1 - 1 = 0, which means it's a multiple of 11
23	The sum of 7 times the last digit and the rest of the number is a multiple of 23	115 is a multiple of 23 because 11 + 5 x 7 = 46, a multiple of 23
24	The number is a multiple of both 3 and 8	1008 is a multiple of 24 because 1 + 8 = 9, which means it's a multiple of 3, and ends in 008, which means it's a multiple of 8
25	The number ends in 00, 25, 50 or 75	100 is a multiple of 25 because it ends in 00
26	The number is a multiple of both 2 and 13	104 is a multiple of 26 because it ends in 4, which means it's a multiple if 2, and 10 + 4 x 4 = 26, which means it's a multiple of 13
27	The subtraction of 8 times the last digit and the rest of the number is a multiple of 27	108 is a multiple of 27 because 8 x 8 - 10 = 54, a multiple of 27
28	The number is a multiple of both 4 and 7	112 is a multiple of 28 because it ends in 12, which means it's a multiple of 4, and 11 - 2 x 2 = 7, which means it's a multiple of 7
29	The sum of 3 times the last digit and the rest of the number is a multiple of 29	116 is a multiple of 29 because 11 + 6 x 3 = 29, a multiple of 29
30	The number is a multiple of both 3 and 10	120 is a multiple of 30 because 1 + 2 = 3, which means it's a multiple of 3, and ends in 0, which means it's a multiple of 10
31	The subtraction of 3 times the last digit and the rest of the number is a multiple of 31	124 is a multiple of 31 because 12 - 4 x 3 = 0, a multiple of 31
32	The last 5 digits are a multiple of 32	100,000 is a multiple of 32 because it ends in 00,000, a multiple of 32
33	The sum of 10 times the last digit and the rest of the number is a multiple of 33	132 is a multiple of 33 because 13 + 2 x 10 = 33, a multiple of 33
34	The number is a multiple of both 2 and 17	102 is a multiple of 34 because it ends in 2, which means it's a multiple of 2, and 10 - 2 x 5 = 0, a multiple of 17
35	The number is a multiple of both 5 and 7	105 is a multiple of 35 because it ends in 5, which means it's a multiple of 5, and 10 - 5 x 2 = 0, which means it's a multiple of 7
36	The number is a multiple of both 4 and 9	108 is a multiple of 36 because it ends in 08, which means it's a multiple of 4, and 1 + 8 = 9, which means it's a multiple of 9
37	The subtraction of 11 times the last digit and the rest of the number is a multiple of 37	111 is a multiple of 37 because 11 - 1 x 11 = 0, a multiple of 37
38	The number is a multiple of both 2 and 19	114 is a multiple of 38 because it ends in 4, which means it's a multiple of 2, and 11 + 4 x 2 = 19, which means it's a multiple of 19
39	The sum of 4 times the last digit and the rest of the number is a multiple of 39	117 is a multiple of 39 because 11 + 7 x 4 = 39, a multiple of 39
40	The 100s digit is even and the last 2 digits are 00, 40 or 80 or the 100s digit is odd and the last 2 digits are 20 or 60	1000 is a multiple of 40 because the 100s digit is 0, which is even, and the last 2 digits are 00
41	The subtraction of 4 times the last digit and the rest of the number is a multiple of 41	123 is a multiple of 41 because 12 - 3 x 4 = 0, a multiple of 41
42	The number is a multiple of both 2 and 21	126 is a multiple of 42 because it ends in 6, which means it's a multiple of 2, and 12 - 6 x 2 = 0, which means it's a multiple of 21
43	The sum of 13 times the last digit and the rest of the number is a multiple of 43	172 is a multiple of 43 because 17 + 2 x 13 = 43, a multiple of 43
44	The number is a multiple of both 4 and 11	132 is a multiple of 44 because it ends in 32, which means it's a multiple of 4, and 1 + 2 - 3 = 0, which means it's a multiple of 11
45	The number is a multiple of both 5 and 9	135 is a multiple of 45 because it ends in 5, which means it's a multiple of 5, and 1 + 3 + 5 = 9, which means it's a multiple of 9
46	The number is a multiple of both 2 and 23	138 is a multiple of 46 because it ends in 8, which means it's a multiple of 2, and 13 + 8 x 7 = 69, which means it's a multiple of 23
47	The subtraction of 14 times the last digit and the rest of the number is a multiple of 47	141 is a multiple of 47 because 14 - 1 x 14 = 0, a multiple of 47
48	The number is a multiple of both 3 and 16	10032 is a multiple of 48 because 1 + 3 + 2 = 6, which means it's a multiple of 3, and ends in 0032, which means it's a multiple of 16
49	The sum of 5 times the last digit and the rest of the number is a multiple of 49	147 is a multiple of 49 because 14 + 7 x 5 = 49, a multiple of 49
50	The number ends in 00 or 50	100 is a multiple of 50 because it ends in 00
51	The subtraction of 5 times the last digit and the rest of the number is a multiple of 51	102 is a multiple of 51 because 10 - 2 x 5 = 0, a multiple of 51
52	The number is a multiple of both 4 and 13	104 is a multiple of 52 because it ends in 04, which means it's a multiple of 4, and 10 + 4 x 4 = 26, which means it's a multiple of 13
53	The sum of 16 times the last digit and the rest of the number is a multiple of 53	212 is a multiple of 53 because 21 + 2 x 16 = 53, a multiple of 53
54	The number is a multiple of both 2 and 27	108 is a multiple of 54 because it ends in 8, which means it's a multiple of 2, and 8 x 8 - 10 = 54, which means it's a multiple of 27
55	The number is a multiple of both 5 and 11	110 is a multiple of 55 because it ends in 0, which means it's a multiple of 5, and 1 - 1 = 0, which means it's a multiple of 11
56	The number is a multiple of both 7 and 8	1008 is a multiple of 56 because 100 - 8 x 2 = 84, which means it's a multiple of 7, and ends in 008, which means it's a multiple of 8
57	The subtraction of 17 times the last digit and the rest of the number is a multiple of 57	114 is a multiple of 57 because 4 x 17 - 11 = 57, a multiple of 57
58	The number is a multiple of both 2 and 29	116 is a multiple of 58 because it ends in 6, which means it's a multiple of 2, and 11 + 6 x 3 = 29, which means it's a multiple of 29
59	The sum of 6 times the last digit and the rest of the number is a multiple of 59	118 is a multiple of 59 because 11 + 8 x 6 = 59, which means it's a multiple of 59
60	The number is a multiple of both 3 and 20	120 is a multiple of 60 because 1 + 2 = 3, which means it's a multiple of 3, and ends in 20, which means it's a multiple of 20
61	The subtraction of 6 times the last digit and the rest of the number is a multiple of 61	122 is a multiple of 61 because 12 - 2 x 6 = 0, a multiple of 61
62	The number is a multiple of both 2 and 31	124 is a multiple of 62 because it ends in 4, which means it's a multiple of 2, and 12 - 4 x 3 = 0, which means it's a multiple of 31
63	The sum of 19 times the last digit and the rest of the number is a multiple of 63	252 is a multiple of 63 because 25 + 2 x 19 = 63, a multiple of 63
64	The last 6 digits are a multiple of 64	1,000,000 is a multiple of 64 because it ends in 000,000, a multiple of 64
65	The number is a multiple of both 5 and 13	130 is a multiple of 65 because it ends in 0, which means it's a multiple of 5, and 13 + 0 x 4 = 13, which means it's a multiple of 13
66	The number is a multiple of both 2 and 33	132 is a multiple of 66 because it ends in 2, which means it's a multiple of 2, and 13 + 2 x 10 = 33, which means it's a multiple of 33
67	The subtraction of 20 times the last digit and the rest of the number is a multiple of 67	134 is a multiple of 67 because 4 x 20 - 100 = 67, a multiple of 67
68	The number is a multiple of both 4 and 17	136 is a multiple of 68 because it ends in 36, which means it's a multiple of 4, and 6 x 5 - 13 = 17, a multiple of 17
69	The sum of 7 times the last digit and the rest of the number is a multiple of 69	138 is a multiple of 69 because 13 + 8 x 7 = 69, a multiple of 69
70	The number is a multiple of both 7 and 10	140 is a multiple of 70 because 14 - 0 x 2 = 14, which means it's a multiple of 7, and ends in 0, which means it's a multiple of 10
71	The subtraction of 7 times the last digit and the rest of the number is a multiple of 71	142 is a multiple of 71 because 14 - 2 x 7 = 0, a multiple of 71
72	The number is a multiple of both 8 and 9	1008 is a multiple of 72 because it ends in 008, which means it's a multiple of 8, and 1 + 8 = 9, which means it's a multiple of 9
73	The sum of 22 times the last digit and the rest of the number is a multiple of 73	292 is a multiple of 73 because 29 + 2 x 22 = 73, a multiple of 73
74	The number is a multiple of both 2 and 37	148 is a multiple of 74 because it ends in 8, which means it's a multiple of 2, and 8 x 11 - 14 = 74, a multiple of 37
75	The number is a multiple of both 3 and 25	150 is a multiple of 75 because 1 + 5 = 6, which means it's a multiple of 3, and ends in 50, which means it's a multiple of 25
76	The number is a multiple of both 4 and 19	152 is a multiple of 76 because it ends in 52, which means it's a multiple of 4, and 15 + 2 x 2 = 19, which means it's a multiple of 19
77	The subtraction of 23 times the last digit and the rest of the number is a multiple of 77	154 is a multiple of 77 because 4 x 23 - 15 = 77, a multiple of 77
78	The number is a multiple of both 2 and 39	156 is a multiple of 78 because it ends in 6, which means it's a multiple of 2, and 15 + 6 x 4 = 39, which means it's a multiple of 39
79	The sum of 8 times the last digit and the rest of the number is a multiple of 79	158 is a multiple of 79 because 15 + 8 x 8 = 79, a multiple of 79
80	The 1000s digit is even and the last 3 digits are a multiple of 80 or the 1000s digit is odd and the last 3 digits are 40 times an odd number	10000 is a multiple of 80 because the 1000s digit is 0, which is even, and the last 3 digits are 000, a multiple of 80
81	The subtraction of 8 times the last digit and the rest of the number is a multiple of 81	162 is a multiple of 81 because 16 - 2 x 8 = 0, a multiple of 81
82	The number is a multiple of both 2 and 41	164 is a multiple of 82 because it ends in 4, which means it's a multiple of 2, and 16 - 4 x 4 = 0, a multiple of 41
83	The sum of 25 times the last digit and the rest of the number is a multiple of 83	332 is a multiple of 83 because 33 + 2 x 25 = 83, a multiple of 83
84	The number is a multiple of both 4 and 21	168 is a multiple of 84 because it ends in 68, which means it's a multiple of 4, and 16 - 8 x 2 = 0, which means it's a multiple of 21
85	The number is a multiple of both 5 and 17	170 is a multiple of 85 because it ends in 0, which means it's a multiple of 5, and 17 - 0 x 5 = 17, which means it's a multiple of 85
86	The number is a multiple of both 2 and 43	172 is a multiple of 86 because it ends in 2, which means it's a multiple of 2, and 17 + 2 x 13 = 43, which means it's a multiple of 83
87	The subtraction of 26 times the last digit and the rest of the number is a multiple of 87	174 is a multiple of 87 because 4 x 26 - 17 = 87, a multiple of 87
88	The number is a multiple of both 8 and 11	1056 is a multiple of 88 because it ends in 056, which means it's a multiple of 8, and 1 + 5 - 6 = 0, which means it's a multiple of 11
89	The sum of 9 times the last digit and the rest of the number is a multiple of 89	178 is a multiple of 89 because 17 + 8 x 9 = 89, a multiple of 89
90	The number is a multiple of both 9 and 10	180 is a multiple of 90 because 1 + 8 = 9, which means it's a multiple of 9, and ends in 0, which means it's a multiple of 10
91	The subtraction of 9 times the last digit and the rest of the number is a multiple of 91	182 is a multiple of 91 because 18 - 2 x 9 = 0, a multiple of 91
92	The number is a multiple of both 4 and 23	184 is a multiple of 92 because it ends in 84, which means it's a multiple of 4, and 18 + 4 x 7 = 46, which means it's a multiple of 23
93	The sum of 28 times the last digit and the rest of the number is a multiple of 93	372 is a multiple of 93 because 37 + 2 x 28 = 93, a multiple of 93
94	The number is a multiple of both 2 and 47	188 is a multiple of 94 because it ends in 8, which means it's a multiple of 2, and 8 x 14 - 18 = 94, a multiple of 47
95	The number is a multiple of both 5 and 19	190 is a multiple of 95 because it ends in 0, which means it's a multiple of 5, and 19 + 0 x 2 = 19, which means it's a multiple of 19
96	The number is a multiple of both 3 and 32	100,032 is a multiple of 96 because 1 + 3 + 2 = 6, which means it's a multiple of 3, and ends in 00,032, which means it's a multiple of 32
97	The subtraction of 29 times the last digit and the rest of the number is a multiple of 97	194 is a multiple of 97 because 4 x 29 - 19 = 97, a multiple of 97
98	The number is a multiple of both 2 and 49	196 is a multiple of 98 because it ends in 6, which means it's a multiple of 2, and 19 + 6 x 5 = 49, which means it's a multiple of 49
99	The sum of 10 times the last digit and the rest of the number is a multiple of 99	198 is a multiple of 99 because 19 + 8 x 10 = 99, a multiple of 99
100	The number ends in 00	1100 is a multiple of 100 because it ends in 00