31971397617 has 12 divisors (see below), whose sum is σ = 47670614784. Its totient is φ = 20626707960.

The previous prime is 31971397609. The next prime is 31971397631. The reversal of 31971397617 is 71679317913.

31971397617 is a `hidden beast` number, since 3 + 1 + 9 + 7 + 13 + 9 + 7 + 617 = 666.

It is not a de Polignac number, because 31971397617 - 2³ = 31971397609 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31971397637) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 57296133 + ... + 57296690.

It is an arithmetic number, because the mean of its divisors is an integer number (3972551232).

Almost surely, 2^31971397617 is an apocalyptic number.

It is an amenable number.

31971397617 is a deficient number, since it is larger than the sum of its proper divisors (15699217167).

31971397617 is a wasteful number, since it uses less digits than its factorization.

31971397617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114592860 (or 114592857 counting only the distinct ones).

The product of its digits is 1500282, while the sum is 54.

The spelling of 31971397617 in words is "thirty-one billion, nine hundred seventy-one million, three hundred ninety-seven thousand, six hundred seventeen".