Divisibility Rules
0 - ends in zero
1 - all numbers
2 - even numbers
3 - sum of the digits is3
4 - divisible by 2, twice
5 - ends in a 0 or 5
6 - divisible by 2 and 3
8 - divisible by 2, thrice
9 - sum of the digits is 9
10 - ends in zero