138936889 has 16 divisors (see below), whose sum is σ = 171279360. Its totient is φ = 109748160.

The previous prime is 138936877. The next prime is 138936893. The reversal of 138936889 is 988639831.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 138936889 - 2⁹ = 138936377 is a prime.

It is not an unprimeable number, because it can be changed into a prime (138936839) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 95832 + ... + 97270.

It is an arithmetic number, because the mean of its divisors is an integer number (10704960).

Almost surely, 2^138936889 is an apocalyptic number.

It is an amenable number.

138936889 is a deficient number, since it is larger than the sum of its proper divisors (32342471).

138936889 is a wasteful number, since it uses less digits than its factorization.

138936889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2520.

The product of its digits is 2239488, while the sum is 55.

The square root of 138936889 is about 11787.1493160984. The cubic root of 138936889 is about 517.9317364564.

The spelling of 138936889 in words is "one hundred thirty-eight million, nine hundred thirty-six thousand, eight hundred eighty-nine".