638585118668 has 12 divisors (see below), whose sum is σ = 1277170237392. Its totient is φ = 273679336560.

The previous prime is 638585118643. The next prime is 638585118701. The reversal of 638585118668 is 866811585836.

638585118668 is an admirable 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, 11403305663 + ... + 11403305718.

It is an arithmetic number, because the mean of its divisors is an integer number (106430853116).

Almost surely, 2^638585118668 is an apocalyptic number.

It is an amenable number.

638585118668 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

638585118668 is a wasteful number, since it uses less digits than its factorization.

638585118668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22806611392 (or 22806611390 counting only the distinct ones).

The product of its digits is 66355200, while the sum is 65.

The spelling of 638585118668 in words is "six hundred thirty-eight billion, five hundred eighty-five million, one hundred eighteen thousand, six hundred sixty-eight".