138867939 has 64 divisors (see below), whose sum is σ = 244346880. Its totient is φ = 77262336.

The previous prime is 138867929. The next prime is 138867947. The reversal of 138867939 is 939768831.

138867939 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 138867939 - 2⁴ = 138867923 is a prime.

It is not an unprimeable number, because it can be changed into a prime (138867929) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 719427 + ... + 719619.

It is an arithmetic number, because the mean of its divisors is an integer number (3817920).

Almost surely, 2^138867939 is an apocalyptic number.

138867939 is a deficient number, since it is larger than the sum of its proper divisors (105478941).

138867939 is an frugal number, since it uses more digits than its factorization.

138867939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 268 (or 250 counting only the distinct ones).

The product of its digits is 1959552, while the sum is 54.

The square root of 138867939 is about 11784.2241577458. The cubic root of 138867939 is about 517.8460445460.

The spelling of 138867939 in words is "one hundred thirty-eight million, eight hundred sixty-seven thousand, nine hundred thirty-nine".