638643714117 has 16 divisors (see below), whose sum is σ = 913965546240. Its totient is φ = 395228339712.

The previous prime is 638643714109. The next prime is 638643714133. The reversal of 638643714117 is 711417346836.

It is not a de Polignac number, because 638643714117 - 2³ = 638643714109 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a self number, because there is not a number n which added to its sum of digits gives 638643714117.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638643714187) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 85766317 + ... + 85773762.

It is an arithmetic number, because the mean of its divisors is an integer number (57122846640).

Almost surely, 2^638643714117 is an apocalyptic number.

It is an amenable number.

638643714117 is a deficient number, since it is larger than the sum of its proper divisors (275321832123).

638643714117 is a wasteful number, since it uses less digits than its factorization.

638643714117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171540172.

The product of its digits is 2032128, while the sum is 51.

The spelling of 638643714117 in words is "six hundred thirty-eight billion, six hundred forty-three million, seven hundred fourteen thousand, one hundred seventeen".