640652904 has 48 divisors (see below), whose sum is σ = 1736280000. Its totient is φ = 213405984.

The previous prime is 640652899. The next prime is 640652959. The reversal of 640652904 is 409256046.

640652904 is a `hidden beast` number, since 640 + 6 + 5 + 2 + 9 + 0 + 4 = 666.

640652904 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×640652904² = 820872286807266432, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 181347 + ... + 184845.

It is an arithmetic number, because the mean of its divisors is an integer number (36172500).

Almost surely, 2^640652904 is an apocalyptic number.

It is an amenable number.

640652904 is an abundant number, since it is smaller than the sum of its proper divisors (1095627096).

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

640652904 is a wasteful number, since it uses less digits than its factorization.

640652904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6054 (or 6047 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 640652904 is about 25311.1221402766. The cubic root of 640652904 is about 862.0668262137.

The spelling of 640652904 in words is "six hundred forty million, six hundred fifty-two thousand, nine hundred four".