31374664921 has 2 divisors, whose sum is σ = 31374664922. Its totient is φ = 31374664920.

The previous prime is 31374664861. The next prime is 31374664931. The reversal of 31374664921 is 12946647313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25649624025 + 5725040896 = 160155^2 + 75664^2 .

It is a cyclic number.

It is not a de Polignac number, because 31374664921 - 2²³ = 31366276313 is a prime.

It is not a weakly prime, because it can be changed into another prime (31374664931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15687332460 + 15687332461.

It is an arithmetic number, because the mean of its divisors is an integer number (15687332461).

Almost surely, 2^31374664921 is an apocalyptic number.

It is an amenable number.

31374664921 is a deficient number, since it is larger than the sum of its proper divisors (1).

31374664921 is an equidigital number, since it uses as much as digits as its factorization.

31374664921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 653184, while the sum is 46.

The spelling of 31374664921 in words is "thirty-one billion, three hundred seventy-four million, six hundred sixty-four thousand, nine hundred twenty-one".