31316281913 has 4 divisors (see below), whose sum is σ = 35790036480. Its totient is φ = 26842527348.

The previous prime is 31316281891. The next prime is 31316281921. The reversal of 31316281913 is 31918261313.

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, and also an emirpimes, since its reverse is a distinct semiprime: 31918261313 = 48533 ⋅657661.

It is not a de Polignac number, because 31316281913 - 2²⁸ = 31047846457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31316281943) 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, 2236877273 + ... + 2236877286.

It is an arithmetic number, because the mean of its divisors is an integer number (8947509120).

Almost surely, 2^31316281913 is an apocalyptic number.

It is an amenable number.

31316281913 is a deficient number, since it is larger than the sum of its proper divisors (4473754567).

31316281913 is an equidigital number, since it uses as much as digits as its factorization.

31316281913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4473754566.

The product of its digits is 23328, while the sum is 38.

The spelling of 31316281913 in words is "thirty-one billion, three hundred sixteen million, two hundred eighty-one thousand, nine hundred thirteen".