31797913 has 6 divisors (see below), whose sum is σ = 36989466. Its totient is φ = 27255312.

The previous prime is 31797907. The next prime is 31797923. The reversal of 31797913 is 31979713.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 26904969 + 4892944 = 5187^2 + 2212^2 .

It is not a de Polignac number, because 31797913 - 2¹³ = 31789721 is a prime.

It is a super-2 number, since 2×31797913² = 2022214542311138, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31797923) 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 5 ways as a sum of consecutive naturals, for example, 324420 + ... + 324517.

It is an arithmetic number, because the mean of its divisors is an integer number (6164911).

Almost surely, 2^31797913 is an apocalyptic number.

It is an amenable number.

31797913 is a deficient number, since it is larger than the sum of its proper divisors (5191553).

31797913 is an equidigital number, since it uses as much as digits as its factorization.

31797913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 648951 (or 648944 counting only the distinct ones).

The product of its digits is 35721, while the sum is 40.

The square root of 31797913 is about 5638.9638232569. The cubic root of 31797913 is about 316.8104795842.

The spelling of 31797913 in words is "thirty-one million, seven hundred ninety-seven thousand, nine hundred thirteen".