138515904 has 42 divisors (see below), whose sum is σ = 397032480. Its totient is φ = 46171776.

The previous prime is 138515899. The next prime is 138515939. The reversal of 138515904 is 409515831.

138515904 is a `hidden beast` number, since 13 + 8 + 51 + 590 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 119664 + ... + 120815.

Almost surely, 2^138515904 is an apocalyptic number.

It is an amenable number.

138515904 is an abundant number, since it is smaller than the sum of its proper divisors (258516576).

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

138515904 is a wasteful number, since it uses less digits than its factorization.

138515904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240497 (or 240484 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 36.

The square root of 138515904 is about 11769.2779727560. The cubic root of 138515904 is about 517.4080884167.

The spelling of 138515904 in words is "one hundred thirty-eight million, five hundred fifteen thousand, nine hundred four".