638583111664 has 40 divisors (see below), whose sum is σ = 1302470208000. Its totient is φ = 302464264896.

The previous prime is 638583111659. The next prime is 638583111709. The reversal of 638583111664 is 466111385836.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4452627 + ... + 4593805.

It is an arithmetic number, because the mean of its divisors is an integer number (32561755200).

Almost surely, 2^638583111664 is an apocalyptic number.

It is an amenable number.

638583111664 is an abundant number, since it is smaller than the sum of its proper divisors (663887096336).

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

638583111664 is a wasteful number, since it uses less digits than its factorization.

638583111664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156085 (or 156079 counting only the distinct ones).

The product of its digits is 2488320, while the sum is 52.

The spelling of 638583111664 in words is "six hundred thirty-eight billion, five hundred eighty-three million, one hundred eleven thousand, six hundred sixty-four".