312631213 has 2 divisors, whose sum is σ = 312631214. Its totient is φ = 312631212.

The previous prime is 312631211. The next prime is 312631217. The reversal of 312631213 is 312136213.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 196056004 + 116575209 = 14002^2 + 10797^2 .

It is an emirp because it is prime and its reverse (312136213) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 312631213 - 2¹ = 312631211 is a prime.

Together with 312631211, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (312631211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156315606 + 156315607.

It is an arithmetic number, because the mean of its divisors is an integer number (156315607).

Almost surely, 2^312631213 is an apocalyptic number.

It is an amenable number.

312631213 is a deficient number, since it is larger than the sum of its proper divisors (1).

312631213 is an equidigital number, since it uses as much as digits as its factorization.

312631213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 648, while the sum is 22.

The square root of 312631213 is about 17681.3804042558. The cubic root of 312631213 is about 678.6993686930.

Adding to 312631213 its reverse (312136213), we get a palindrome (624767426).

The spelling of 312631213 in words is "three hundred twelve million, six hundred thirty-one thousand, two hundred thirteen".