What is the fewest number of factors a composite number can have?

Answer 1

The fewest number of factors that a composite number can have is 3 factors. Let's check it out. If we look at prime numbers, they have only 1 and themselves as factors. That's 2 factors. But if we look at something like 4 or 9, they each have a single other factor because they are squares. If we look at 4, its factors are 1, 2 and 4. That's because 1 x 4 = 4 and 2 x 2 = 4. If we look at 9, its factors are 1, 3 and 9. It can be seen that 1 x 9 = 9 and also that 3 x 3 = 9. Given those examples, is it true that composite numbers that have only 3 factors are all squares? But that's another question!