31890207956 has 6 divisors (see below), whose sum is σ = 55807863930. Its totient is φ = 15945103976.

The previous prime is 31890207931. The next prime is 31890207977. The reversal of 31890207956 is 65970209813.

It can be written as a sum of positive squares in only one way, i.e., 30324739600 + 1565468356 = 174140^2 + 39566^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3986275991 + ... + 3986275998.

It is an arithmetic number, because the mean of its divisors is an integer number (9301310655).

Almost surely, 2^31890207956 is an apocalyptic number.

It is an amenable number.

31890207956 is a deficient number, since it is larger than the sum of its proper divisors (23917655974).

31890207956 is a wasteful number, since it uses less digits than its factorization.

31890207956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7972551993 (or 7972551991 counting only the distinct ones).

The product of its (nonzero) digits is 816480, while the sum is 50.

The spelling of 31890207956 in words is "thirty-one billion, eight hundred ninety million, two hundred seven thousand, nine hundred fifty-six".