640204408 has 16 divisors (see below), whose sum is σ = 1201149000. Its totient is φ = 319898016.

The previous prime is 640204391. The next prime is 640204417. The reversal of 640204408 is 804402046.

640204408 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11763 + ... + 37666.

Almost surely, 2^640204408 is an apocalyptic number.

It is an amenable number.

640204408 is a deficient number, since it is larger than the sum of its proper divisors (560944592).

640204408 is a wasteful number, since it uses less digits than its factorization.

640204408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51054 (or 51050 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 28.

The square root of 640204408 is about 25302.2609266445. The cubic root of 640204408 is about 861.8656128482.

The spelling of 640204408 in words is "six hundred forty million, two hundred four thousand, four hundred eight".