638011636900 has 72 divisors (see below), whose sum is σ = 1525301749440. Its totient is φ = 229707120000.

The previous prime is 638011636849. The next prime is 638011636931. The reversal of 638011636900 is 9636110836.

It is a super-2 number, since 2×638011636900² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2760240 + ... + 2982439.

It is an arithmetic number, because the mean of its divisors is an integer number (21184746520).

Almost surely, 2^638011636900 is an apocalyptic number.

It is an amenable number.

638011636900 is an abundant number, since it is smaller than the sum of its proper divisors (887290112540).

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

638011636900 is a wasteful number, since it uses less digits than its factorization.

638011636900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5742805 (or 5742798 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 43.

The spelling of 638011636900 in words is "six hundred thirty-eight billion, eleven million, six hundred thirty-six thousand, nine hundred".