The sum of all positive divisors of 242 except 1 and itself is.

The sum of all positive divisors of 242 except 1 and self is

The number of positive divisors of 252 is

The number of positive divisors of 2520 is

We call a number perfect if it is the sum of all its positive divisors, except itself. e.g. 28 is a perfect number because 28=1+2+4+7+14 . Which of the following numbers is a perfect number?