638355544872 has 64 divisors (see below), whose sum is σ = 1651564296000. Its totient is φ = 205367522304.

The previous prime is 638355544777. The next prime is 638355544973. The reversal of 638355544872 is 278445553836.

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 15 ways as a sum of consecutive naturals, for example, 1617168 + ... + 1972800.

It is an arithmetic number, because the mean of its divisors is an integer number (25805692125).

Almost surely, 2^638355544872 is an apocalyptic number.

It is an amenable number.

638355544872 is an abundant number, since it is smaller than the sum of its proper divisors (1013208751128).

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

638355544872 is a wasteful number, since it uses less digits than its factorization.

638355544872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 358250 (or 358246 counting only the distinct ones).

The product of its digits is 96768000, while the sum is 60.

The spelling of 638355544872 in words is "six hundred thirty-eight billion, three hundred fifty-five million, five hundred forty-four thousand, eight hundred seventy-two".