Perfect
Number
A number n for which the sum of all
the positive integer factors of
n which are less than n add up to n.
For example,
6 and 28 are perfect numbers. The number 6 has factors 1, 2,
and 3, and 1 + 2 + 3 = 6. The number 28 has factors 1, 2, 4, 7,
and 14, and 1
+ 2
+ 4 + 7 + 14 = 28.
