31680002861 has 4 divisors (see below), whose sum is σ = 34116926172. Its totient is φ = 29243079552.

The previous prime is 31680002819. The next prime is 31680002891. The reversal of 31680002861 is 16820008613.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9301638025 + 22378364836 = 96445^2 + 149594^2 .

It is a cyclic number.

It is not a de Polignac number, because 31680002861 - 2²² = 31675808557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31680002801) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1218461636 + ... + 1218461661.

It is an arithmetic number, because the mean of its divisors is an integer number (8529231543).

Almost surely, 2^31680002861 is an apocalyptic number.

It is an amenable number.

31680002861 is a deficient number, since it is larger than the sum of its proper divisors (2436923311).

31680002861 is a wasteful number, since it uses less digits than its factorization.

31680002861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2436923310.

The product of its (nonzero) digits is 13824, while the sum is 35.

The spelling of 31680002861 in words is "thirty-one billion, six hundred eighty million, two thousand, eight hundred sixty-one".