31131323013 has 16 divisors (see below), whose sum is σ = 49074007680. Its totient is φ = 17175902016.

The previous prime is 31131322979. The next prime is 31131323017. The reversal of 31131323013 is 31032313113.

It is not a de Polignac number, because 31131323013 - 2⁶ = 31131322949 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31131323017) 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, 25558770 + ... + 25559987.

It is an arithmetic number, because the mean of its divisors is an integer number (3067125480).

Almost surely, 2^31131323013 is an apocalyptic number.

It is an amenable number.

31131323013 is a deficient number, since it is larger than the sum of its proper divisors (17942684667).

31131323013 is a wasteful number, since it uses less digits than its factorization.

31131323013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51118796.

The product of its (nonzero) digits is 486, while the sum is 21.

Adding to 31131323013 its reverse (31032313113), we get a palindrome (62163636126).

The spelling of 31131323013 in words is "thirty-one billion, one hundred thirty-one million, three hundred twenty-three thousand, thirteen".