638403576857 has 8 divisors (see below), whose sum is σ = 643468158432. Its totient is φ = 633341893600.

The previous prime is 638403576817. The next prime is 638403576929. The reversal of 638403576857 is 758675304836.

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

It is a cyclic number.

It is not a de Polignac number, because 638403576857 - 2¹⁰ = 638403575833 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 638403576857.

It is not an unprimeable number, because it can be changed into a prime (638403576817) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 281228 + ... + 1164429.

It is an arithmetic number, because the mean of its divisors is an integer number (80433519804).

Almost surely, 2^638403576857 is an apocalyptic number.

It is an amenable number.

638403576857 is a deficient number, since it is larger than the sum of its proper divisors (5064581575).

638403576857 is a wasteful number, since it uses less digits than its factorization.

638403576857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1449159.

The product of its (nonzero) digits is 101606400, while the sum is 62.

The spelling of 638403576857 in words is "six hundred thirty-eight billion, four hundred three million, five hundred seventy-six thousand, eight hundred fifty-seven".