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:
“People understand God as the expression of the most lofty morality. Maybe He needs only perfect people.”
—Anton Pavlovich Chekhov (1860–1904)
“In proportion as our inward life fails, we go more constantly and desperately to the post office. You may depend on it, that the poor fellow who walks away with the greatest number of letters, proud of his extensive correspondence, has not heard from himself this long while.”
—Henry David Thoreau (1817–1862)