638632384708 has 72 divisors (see below), whose sum is σ = 1189864672920. Its totient is φ = 299770099200.

The previous prime is 638632384697. The next prime is 638632384711. The reversal of 638632384708 is 807483236836.

It can be written as a sum of positive squares in 4 ways, for example, as 203781822084 + 434850562624 = 451422^2 + 659432^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 18114538 + ... + 18149758.

It is an arithmetic number, because the mean of its divisors is an integer number (16525898235).

Almost surely, 2^638632384708 is an apocalyptic number.

It is an amenable number.

638632384708 is a deficient number, since it is larger than the sum of its proper divisors (551232288212).

638632384708 is a wasteful number, since it uses less digits than its factorization.

638632384708 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35429 (or 35396 counting only the distinct ones).

The product of its (nonzero) digits is 27869184, while the sum is 58.

The spelling of 638632384708 in words is "six hundred thirty-eight billion, six hundred thirty-two million, three hundred eighty-four thousand, seven hundred eight".