138923655 has 16 divisors (see below), whose sum is σ = 239376480. Its totient is φ = 68393088.

The previous prime is 138923639. The next prime is 138923683. The reversal of 138923655 is 556329831.

138923655 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 138923655 - 2⁴ = 138923639 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 356020 + ... + 356409.

It is an arithmetic number, because the mean of its divisors is an integer number (14961030).

Almost surely, 2^138923655 is an apocalyptic number.

138923655 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

138923655 is a deficient number, since it is larger than the sum of its proper divisors (100452825).

138923655 is a wasteful number, since it uses less digits than its factorization.

138923655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 712450.

The product of its digits is 194400, while the sum is 42.

The square root of 138923655 is about 11786.5879286586. The cubic root of 138923655 is about 517.9152912769.

The spelling of 138923655 in words is "one hundred thirty-eight million, nine hundred twenty-three thousand, six hundred fifty-five".