Quasiperfect Number

In mathematics, a quasiperfect number is a theoretical natural number n for which the sum of all its divisors (the divisor function σ(n)) is equal to 2n + 1. Quasiperfect numbers are abundant numbers.

No quasiperfect numbers have been found so far, but if a quasiperfect number exists, it must be an odd square number greater than 1035 and have at least seven distinct prime factors.

Famous quotes containing the word number:

    I have known a number of Don Juans who were good studs and who cavorted between the sheets without a psychiatrist to guide them. But most of the busy love-makers I knew were looking for masculinity rather than practicing it. They were fellows of dubious lust.
    Ben Hecht (1893–1964)