638657064877 has 8 divisors (see below), whose sum is σ = 692732623520. Its totient is φ = 585288376560.

The previous prime is 638657064827. The next prime is 638657064887. The reversal of 638657064877 is 778460756836.

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 638657064877 - 2¹⁵ = 638657032109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638657064827) 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, 176715699 + ... + 176719312.

It is an arithmetic number, because the mean of its divisors is an integer number (86591577940).

Almost surely, 2^638657064877 is an apocalyptic number.

It is an amenable number.

638657064877 is a deficient number, since it is larger than the sum of its proper divisors (54075558643).

638657064877 is a wasteful number, since it uses less digits than its factorization.

638657064877 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 353435163.

The product of its (nonzero) digits is 284497920, while the sum is 67.

The spelling of 638657064877 in words is "six hundred thirty-eight billion, six hundred fifty-seven million, sixty-four thousand, eight hundred seventy-seven".