638117118 has 12 divisors (see below), whose sum is σ = 1382587128. Its totient is φ = 212705700.

The previous prime is 638117111. The next prime is 638117141. The reversal of 638117118 is 811711836.

It is a happy number.

638117118 is a `hidden beast` number, since 638 + 1 + 1 + 7 + 1 + 18 = 666.

638117118 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638117111) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 17725458 + ... + 17725493.

It is an arithmetic number, because the mean of its divisors is an integer number (115215594).

Almost surely, 2^638117118 is an apocalyptic number.

638117118 is an abundant number, since it is smaller than the sum of its proper divisors (744470010).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

638117118 is a wasteful number, since it uses less digits than its factorization.

638117118 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35450959 (or 35450956 counting only the distinct ones).

The product of its digits is 8064, while the sum is 36.

The square root of 638117118 is about 25260.9801472548. The cubic root of 638117118 is about 860.9279320676.

The spelling of 638117118 in words is "six hundred thirty-eight million, one hundred seventeen thousand, one hundred eighteen".