noun
: an integer (as 6) the sum of whose divisors including 1 but excluding itself is equal to itself
28, which . 1 + 2 + 4 + 7 + 14, is a perfect number
— compare imperfect number
noun
: an integer (as 6) the sum of whose divisors including 1 but excluding itself is equal to itself
28, which . 1 + 2 + 4 + 7 + 14, is a perfect number
— compare imperfect number
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012