Chapter 5, Lesson 4

In their study of number theory, Bea and Jay have learned that:

The proper factors of a positive integer are all of its factors except for the integer itself.

If the sum of the proper factors:
= the number, then the number is perfect.
> the number, then the number is abundant.
< the number, then the number is deficient.

Today, Bea and Jay learned that if a number is abundant and you can find a set of fewer than all of its proper factors that add up to the number, then the number is called semiperfect.

Bea said that 12 is an example of a semiperfect number. Do you agree or disagree? Explain.

Now you find a number less than or equal to 30 that is semiperfect.