1 and 19.
One.
Fifty-seven divided by three is 19, therefore three goes in evenly. If it goes in evenly, it is divisible.
19 and 2
1, 7, 19, 133.
1, 2, 19, 38.
1, 5, 19, and 95.
1, 7, 19, 133.
Each of these numbers goes evenly into 133: 1, 7, 19, 133.
1, 2, 4, 19, 38 and 76.
None, they're both prime numbers.
In this case, 1 is the only common multiple of 19 and 100 because 19 is odd and 100 is even.
Each of these numbers goes evenly into 475: 1, 5, 19, 25, 95, 475.