A positive integer with three distinct prime divisors cannot have how many total factors?

What do you think about this one?

I am not understanding this solutions

Have you attempted the problem?


Yes. I have been attempted this problem also seeing the solution. In this solution greg try multiply extra 2. I can’t understand why extra 2 are added

Total factors = positive plus negative factors. This is a notorious issue we have here.

Edit: the question has been adjusted to eliminate this confusion.