For problem number 2: 1,3,5,15
For Problem number 3: 1,2,3,4,5,6,10,12,15,20,30,60
For problem number 4: 1,3,6
For problem number 5: 1,2,3,4,6,12
For problem number 6: 1, 2, 3, 4, 6, 9, 12, 18, 36
For problem number 7: 3
For problem number 8: 4
For problem number 9: 4
For problem number 10: 3
For problem number 11: 5
For problem number 12: 3
Sorry but i didn't answer number 17 and 18
