Four of them.
60 and 90 are the numbers between 50 and 100 that are factors of 180
50
25 of them.
100 has nine factors.
4, 9, 25, and 49 are all of the numbers between 1 and 100 having 3 factors.
There aren't any numbers between 1 and 100 with 16 factors.
180, which has 18 factors.
No numbers between 1 and 100 have exactly eleven factors. 60, 72, 84, 90 and 96 each have twelve factors.
The factors of 3 are 1 and 3.
Nine
There are 99 numbers between 0 and 100.