15312139 has 4 divisors (see below), whose sum is σ = 15333280. Its totient is φ = 15291000.

The previous prime is 15312131. The next prime is 15312149. The reversal of 15312139 is 93121351.

15312139 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 15312139 - 2³ = 15312131 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15312131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9444 + ... + 10945.

It is an arithmetic number, because the mean of its divisors is an integer number (3833320).

Almost surely, 2^15312139 is an apocalyptic number.

15312139 is a deficient number, since it is larger than the sum of its proper divisors (21141).

15312139 is an equidigital number, since it uses as much as digits as its factorization.

15312139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21140.

The product of its digits is 810, while the sum is 25.

The square root of 15312139 is about 3913.0728334648. The cubic root of 15312139 is about 248.3201456394.

It can be divided in two parts, 15312 and 139, that added together give a palindrome (15451).

The spelling of 15312139 in words is "fifteen million, three hundred twelve thousand, one hundred thirty-nine".