31231013 has 4 divisors (see below), whose sum is σ = 34070208. Its totient is φ = 28391820.

The previous prime is 31231009. The next prime is 31231027. The reversal of 31231013 is 31013213.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 31231013 - 2² = 31231009 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 (31231063) 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, 1419581 + ... + 1419602.

It is an arithmetic number, because the mean of its divisors is an integer number (8517552).

Almost surely, 2^31231013 is an apocalyptic number.

It is an amenable number.

31231013 is a deficient number, since it is larger than the sum of its proper divisors (2839195).

31231013 is a wasteful number, since it uses less digits than its factorization.

31231013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2839194.

The product of its (nonzero) digits is 54, while the sum is 14.

The square root of 31231013 is about 5588.4714368063. The cubic root of 31231013 is about 314.9164572270.

Adding to 31231013 its reverse (31013213), we get a palindrome (62244226).

The spelling of 31231013 in words is "thirty-one million, two hundred thirty-one thousand, thirteen".