638580885638 has 16 divisors (see below), whose sum is σ = 978275349504. Its totient is φ = 312489432840.

The previous prime is 638580885629. The next prime is 638580885661. The reversal of 638580885638 is 836588085836.

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, 7255073 + ... + 7342563.

It is an arithmetic number, because the mean of its divisors is an integer number (61142209344).

Almost surely, 2^638580885638 is an apocalyptic number.

638580885638 is a deficient number, since it is larger than the sum of its proper divisors (339694463866).

638580885638 is a wasteful number, since it uses less digits than its factorization.

638580885638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165187.

The product of its (nonzero) digits is 265420800, while the sum is 68.

The spelling of 638580885638 in words is "six hundred thirty-eight billion, five hundred eighty million, eight hundred eighty-five thousand, six hundred thirty-eight".