31013913 has 24 divisors (see below), whose sum is σ = 50200128. Its totient is φ = 16949856.

The previous prime is 31013911. The next prime is 31013929. The reversal of 31013913 is 31931013.

It is not a de Polignac number, because 31013913 - 2¹ = 31013911 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a self number, because there is not a number n which added to its sum of digits gives 31013913.

It is not an unprimeable number, because it can be changed into a prime (31013911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1206 + ... + 7967.

It is an arithmetic number, because the mean of its divisors is an integer number (2091672).

Almost surely, 2^31013913 is an apocalyptic number.

It is an amenable number.

31013913 is a deficient number, since it is larger than the sum of its proper divisors (19186215).

31013913 is a wasteful number, since it uses less digits than its factorization.

31013913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9213 (or 9206 counting only the distinct ones).

The product of its (nonzero) digits is 243, while the sum is 21.

The square root of 31013913 is about 5569.0136469576. The cubic root of 31013913 is about 314.1850539404.

Adding to 31013913 its reverse (31931013), we get a palindrome (62944926).

The spelling of 31013913 in words is "thirty-one million, thirteen thousand, nine hundred thirteen".