640500064 has 24 divisors (see below), whose sum is σ = 1261596168. Its totient is φ = 320094720.

The previous prime is 640500059. The next prime is 640500097. The reversal of 640500064 is 460005046.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 91704 + ... + 98440.

It is an arithmetic number, because the mean of its divisors is an integer number (52566507).

Almost surely, 2^640500064 is an apocalyptic number.

It is an amenable number.

640500064 is a deficient number, since it is larger than the sum of its proper divisors (621096104).

640500064 is a wasteful number, since it uses less digits than its factorization.

640500064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9718 (or 9710 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 640500064 is about 25308.1027341047. The cubic root of 640500064 is about 861.9982665864.

The spelling of 640500064 in words is "six hundred forty million, five hundred thousand, sixty-four".