Which positive integer less than 100 has the most proper factors?

Sometimes the number 1 is included in the proper factors, and sometimes it is not. In the list of factors I have included the number 1. The following numbers have 10 or 11 proper factors, depending on whether 1 is allowed as a proper factor.

The factors of 60 are 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30.

The factors of 72 are 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36.

The factors of 84 are 1, 2, 3, 4, 6, 7, 12, 14, 21, 28, 42.

The factors of 90 are 1, 2, 3, 5, 6, 9, 10, 15, 18, 30, 45.

The factors of 96 are 1, 2, 3, 4, 6, 8, 12, 16, 24, 32, 48.