An
integer which is
equal to the
sum of its
positive divisors. The first three are:
6 = 1 + 2 + 3
28 = 1 + 2 + 4 + 7 + 14
496 = 1 + 2 + 4 + 8 + 16 + 31 + 62 + 124 + 248
It is
unknown if there are any
odd perfect numbers. Many
cultures
throughout
history have ascribed
religious and
mystical significance
to these numbers.