638680815676 has 12 divisors (see below), whose sum is σ = 1125093358480. Its totient is φ = 317225570400.

The previous prime is 638680815659. The next prime is 638680815709. The reversal of 638680815676 is 676518086836.

638680815676 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, 528708681 + ... + 528709888.

Almost surely, 2^638680815676 is an apocalyptic number.

It is an amenable number.

638680815676 is a deficient number, since it is larger than the sum of its proper divisors (486412542804).

638680815676 is a wasteful number, since it uses less digits than its factorization.

638680815676 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1057418724 (or 1057418722 counting only the distinct ones).

The product of its (nonzero) digits is 69672960, while the sum is 64.

The spelling of 638680815676 in words is "six hundred thirty-eight billion, six hundred eighty million, eight hundred fifteen thousand, six hundred seventy-six".