31512991690 has 32 divisors (see below), whose sum is σ = 59847517440. Its totient is φ = 11914027200.

The previous prime is 31512991661. The next prime is 31512991721. The reversal of 31512991690 is 9619921513.

It is a happy number.

It is a super-2 number, since 2×31512991690² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 31512991690.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 110521 + ... + 274300.

It is an arithmetic number, because the mean of its divisors is an integer number (1870234920).

Almost surely, 2^31512991690 is an apocalyptic number.

31512991690 is a deficient number, since it is larger than the sum of its proper divisors (28334525750).

31512991690 is a wasteful number, since it uses less digits than its factorization.

31512991690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 385278.

The product of its (nonzero) digits is 131220, while the sum is 46.

The spelling of 31512991690 in words is "thirty-one billion, five hundred twelve million, nine hundred ninety-one thousand, six hundred ninety".