640635323056 has 20 divisors (see below), whose sum is σ = 1314244523592. Its totient is φ = 301475446016.

The previous prime is 640635323047. The next prime is 640635323087. The reversal of 640635323056 is 650323536046.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1177638190 + ... + 1177638733.

Almost surely, 2^640635323056 is an apocalyptic number.

It is an amenable number.

640635323056 is an abundant number, since it is smaller than the sum of its proper divisors (673609200536).

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

640635323056 is a wasteful number, since it uses less digits than its factorization.

640635323056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2355276948 (or 2355276942 counting only the distinct ones).

The product of its (nonzero) digits is 1166400, while the sum is 43.

The spelling of 640635323056 in words is "six hundred forty billion, six hundred thirty-five million, three hundred twenty-three thousand, fifty-six".