138904997 has 32 divisors (see below), whose sum is σ = 178723584. Its totient is φ = 104832000.

The previous prime is 138904967. The next prime is 138904999. The reversal of 138904997 is 799409831.

It is not a de Polignac number, because 138904997 - 2⁸ = 138904741 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138904999) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 412013 + ... + 412349.

It is an arithmetic number, because the mean of its divisors is an integer number (5585112).

Almost surely, 2^138904997 is an apocalyptic number.

It is an amenable number.

138904997 is a deficient number, since it is larger than the sum of its proper divisors (39818587).

138904997 is a wasteful number, since it uses less digits than its factorization.

138904997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 509.

The product of its (nonzero) digits is 489888, while the sum is 50.

The square root of 138904997 is about 11785.7964092377. The cubic root of 138904997 is about 517.8921042103.

The spelling of 138904997 in words is "one hundred thirty-eight million, nine hundred four thousand, nine hundred ninety-seven".