638861716166 has 8 divisors (see below), whose sum is σ = 958312063200. Its totient is φ = 319424361768.

The previous prime is 638861716139. The next prime is 638861716189. The reversal of 638861716166 is 661617168836.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a congruent 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, 3124286 + ... + 3322481.

It is an arithmetic number, because the mean of its divisors is an integer number (119789007900).

Almost surely, 2^638861716166 is an apocalyptic number.

638861716166 is a deficient number, since it is larger than the sum of its proper divisors (319450347034).

638861716166 is a wasteful number, since it uses less digits than its factorization.

638861716166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6496318.

The product of its digits is 10450944, while the sum is 59.

The spelling of 638861716166 in words is "six hundred thirty-eight billion, eight hundred sixty-one million, seven hundred sixteen thousand, one hundred sixty-six".