31381667856 has 120 divisors (see below), whose sum is σ = 109496247744. Its totient is φ = 8151079680.

The previous prime is 31381667819. The next prime is 31381667857. The reversal of 31381667856 is 65876618313.

It is not an unprimeable number, because it can be changed into a prime (31381667857) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1404031 + ... + 1426206.

Almost surely, 2^31381667856 is an apocalyptic number.

31381667856 is a gapful number since it is divisible by the number (36) formed by its first and last digit.

It is an amenable number.

31381667856 is an abundant number, since it is smaller than the sum of its proper divisors (78114579888).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31381667856 is a wasteful number, since it uses less digits than its factorization.

31381667856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2830269 (or 2830260 counting only the distinct ones).

The product of its digits is 4354560, while the sum is 54.

The spelling of 31381667856 in words is "thirty-one billion, three hundred eighty-one million, six hundred sixty-seven thousand, eight hundred fifty-six".