138956279 has 12 divisors (see below), whose sum is σ = 174557712. Its totient is φ = 108276960.

The previous prime is 138956243. The next prime is 138956297. The reversal of 138956279 is 972659831.

138956279 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 138956279 - 2²⁰ = 137907703 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138956479) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 81182 + ... + 82875.

It is an arithmetic number, because the mean of its divisors is an integer number (14546476).

Almost surely, 2^138956279 is an apocalyptic number.

138956279 is a deficient number, since it is larger than the sum of its proper divisors (35601433).

138956279 is a wasteful number, since it uses less digits than its factorization.

138956279 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164086 (or 164075 counting only the distinct ones).

The product of its digits is 816480, while the sum is 50.

The square root of 138956279 is about 11787.9717933154. The cubic root of 138956279 is about 517.9558294800.

The spelling of 138956279 in words is "one hundred thirty-eight million, nine hundred fifty-six thousand, two hundred seventy-nine".