312531431 has 2 divisors, whose sum is σ = 312531432. Its totient is φ = 312531430.

The previous prime is 312531413. The next prime is 312531481. The reversal of 312531431 is 134135213.

Together with previous prime (312531413) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is an emirp because it is prime and its reverse (134135213) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-312531431 is a prime.

It is a super-2 number, since 2×312531431² = 195351790725815522, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 312531397 and 312531406.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (312531481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156265715 + 156265716.

It is an arithmetic number, because the mean of its divisors is an integer number (156265716).

Almost surely, 2^312531431 is an apocalyptic number.

312531431 is a deficient number, since it is larger than the sum of its proper divisors (1).

312531431 is an equidigital number, since it uses as much as digits as its factorization.

312531431 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1080, while the sum is 23.

The square root of 312531431 is about 17678.5585102406. The cubic root of 312531431 is about 678.6271545487.

Adding to 312531431 its reverse (134135213), we get a palindrome (446666644).

The spelling of 312531431 in words is "three hundred twelve million, five hundred thirty-one thousand, four hundred thirty-one".