13139931 has 16 divisors (see below), whose sum is σ = 20450304. Its totient is φ = 7348224.

The previous prime is 13139909. The next prime is 13139941. The reversal of 13139931 is 13993131.

It is a happy number.

13139931 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 13139931 - 2¹⁵ = 13107163 is a prime.

It is a super-2 number, since 2×13139931² = 345315573369522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (13139941) 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, 5670 + ... + 7643.

It is an arithmetic number, because the mean of its divisors is an integer number (1278144).

Almost surely, 2^13139931 is an apocalyptic number.

13139931 is a deficient number, since it is larger than the sum of its proper divisors (7310373).

13139931 is a wasteful number, since it uses less digits than its factorization.

13139931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13370.

The product of its digits is 2187, while the sum is 30.

The square root of 13139931 is about 3624.9042745982. The cubic root of 13139931 is about 235.9741125966.

The spelling of 13139931 in words is "thirteen million, one hundred thirty-nine thousand, nine hundred thirty-one".