640510172 has 12 divisors (see below), whose sum is σ = 1144741920. Its totient is φ = 313441056.

The previous prime is 640510111. The next prime is 640510259. The reversal of 640510172 is 271015046.

640510172 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, 1703297 + ... + 1703672.

It is an arithmetic number, because the mean of its divisors is an integer number (95395160).

Almost surely, 2^640510172 is an apocalyptic number.

It is an amenable number.

640510172 is a deficient number, since it is larger than the sum of its proper divisors (504231748).

640510172 is a wasteful number, since it uses less digits than its factorization.

640510172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3407020 (or 3407018 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 640510172 is about 25308.3024322059. The cubic root of 640510172 is about 862.0028010812.

The spelling of 640510172 in words is "six hundred forty million, five hundred ten thousand, one hundred seventy-two".