312931 has 2 divisors, whose sum is σ = 312932. Its totient is φ = 312930.

The previous prime is 312929. The next prime is 312937. The reversal of 312931 is 139213.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 312931 - 2¹ = 312929 is a prime.

It is a super-2 number, since 2×312931² = 195851621522, which contains 22 as substring.

Together with 312929, it forms a pair of twin primes.

It is a Chen prime.

312931 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 312899 and 312908.

It is not a weakly prime, because it can be changed into another prime (312937) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156465 + 156466.

It is an arithmetic number, because the mean of its divisors is an integer number (156466).

2³¹²⁹³¹ is an apocalyptic number.

312931 is a deficient number, since it is larger than the sum of its proper divisors (1).

312931 is an equidigital number, since it uses as much as digits as its factorization.

312931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 162, while the sum is 19.

The square root of 312931 is about 559.4023596661. The cubic root of 312931 is about 67.8916237897.

It can be divided in two parts, 3129 and 31, that added together give a triangular number (3160 = T₇₉).

The spelling of 312931 in words is "three hundred twelve thousand, nine hundred thirty-one".