31897684511 has 16 divisors (see below), whose sum is σ = 42107869440. Its totient is φ = 23393258880.

The previous prime is 31897684501. The next prime is 31897684513. The reversal of 31897684511 is 11548679813.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31897684511 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31897684513) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12182681 + ... + 12185298.

It is an arithmetic number, because the mean of its divisors is an integer number (2631741840).

Almost surely, 2^31897684511 is an apocalyptic number.

31897684511 is a deficient number, since it is larger than the sum of its proper divisors (10210184929).

31897684511 is a wasteful number, since it uses less digits than its factorization.

31897684511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24368014.

The product of its digits is 1451520, while the sum is 53.

The spelling of 31897684511 in words is "thirty-one billion, eight hundred ninety-seven million, six hundred eighty-four thousand, five hundred eleven".