In number theory, a perfect number is a positive integer that is equal to the sum of its proper positive divisors, that is, the sum of its positive divisors excluding the number itself (also known as its aliquot sum). Equivalently, a perfect number is a number that is half the sum of all of its positive divisors (including itself) i.e. σ1(n) = 2n.
Read more about Perfect Number: Examples, Discovery, Even Perfect Numbers, Odd Perfect Numbers, Minor Results, Related Concepts
Famous quotes containing the words perfect and/or number:
“This is not to say that becoming a father automatically makes you a good father. Fatherhood, like marriage, is a constant struggle against your limitations and self-interests. But the urge to be a perfect father is there, because your child is a perfect gift.”
—Kent Nerburn (20th century)
“Nothing ever prepares a couple for having a baby, especially the first one. And even baby number two or three, the surprises and challenges, the cosmic curve balls, keep on coming. We can’t believe how much children change everything—the time we rise and the time we go to bed; the way we fight and the way we get along. Even when, and if, we make love.”
—Susan Lapinski (20th century)