138920915 has 32 divisors (see below), whose sum is σ = 196922880. Its totient is φ = 92102400.

The previous prime is 138920893. The next prime is 138920921. The reversal of 138920915 is 519029831.

138920915 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 138920915 - 2¹⁴ = 138904531 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 187616 + ... + 188354.

It is an arithmetic number, because the mean of its divisors is an integer number (6153840).

Almost surely, 2^138920915 is an apocalyptic number.

138920915 is a deficient number, since it is larger than the sum of its proper divisors (58001965).

138920915 is a wasteful number, since it uses less digits than its factorization.

138920915 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 923.

The product of its (nonzero) digits is 19440, while the sum is 38.

The square root of 138920915 is about 11786.4716942773. The cubic root of 138920915 is about 517.9118862959.

The spelling of 138920915 in words is "one hundred thirty-eight million, nine hundred twenty thousand, nine hundred fifteen".