640259500 has 24 divisors (see below), whose sum is σ = 1398327840. Its totient is φ = 256103600.

The previous prime is 640259467. The next prime is 640259519. The reversal of 640259500 is 5952046.

640259500 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 639760 + ... + 640759.

It is an arithmetic number, because the mean of its divisors is an integer number (58263660).

Almost surely, 2^640259500 is an apocalyptic number.

It is an amenable number.

640259500 is an abundant number, since it is smaller than the sum of its proper divisors (758068340).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

640259500 is a wasteful number, since it uses less digits than its factorization.

640259500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1280538 (or 1280526 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 31.

The square root of 640259500 is about 25303.3495806385. The cubic root of 640259500 is about 861.8903343995.

The spelling of 640259500 in words is "six hundred forty million, two hundred fifty-nine thousand, five hundred".