31213631213 has 2 divisors, whose sum is σ = 31213631214. Its totient is φ = 31213631212.

The previous prime is 31213631209. The next prime is 31213631227.

31213631213 is nontrivially palindromic in base 10.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24837129604 + 6376501609 = 157598^2 + 79853^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 31213631213 - 2² = 31213631209 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31213631513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15606815606 + 15606815607.

It is an arithmetic number, because the mean of its divisors is an integer number (15606815607).

Almost surely, 2^31213631213 is an apocalyptic number.

It is an amenable number.

31213631213 is a deficient number, since it is larger than the sum of its proper divisors (1).

31213631213 is an equidigital number, since it uses as much as digits as its factorization.

31213631213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1944, while the sum is 26.

The spelling of 31213631213 in words is "thirty-one billion, two hundred thirteen million, six hundred thirty-one thousand, two hundred thirteen".