31686312 has 32 divisors (see below), whose sum is σ = 90532800. Its totient is φ = 9053184.

The previous prime is 31686289. The next prime is 31686349. The reversal of 31686312 is 21368613.

It is a super-2 number, since 2×31686312² = 2008044736322688, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 31686312.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 94137 + ... + 94472.

It is an arithmetic number, because the mean of its divisors is an integer number (2829150).

Almost surely, 2^31686312 is an apocalyptic number.

It is an amenable number.

31686312 is an abundant number, since it is smaller than the sum of its proper divisors (58846488).

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

31686312 is a wasteful number, since it uses less digits than its factorization.

31686312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188625 (or 188621 counting only the distinct ones).

The product of its digits is 5184, while the sum is 30.

The square root of 31686312 is about 5629.0596017452. The cubic root of 31686312 is about 316.4394089992.

The spelling of 31686312 in words is "thirty-one million, six hundred eighty-six thousand, three hundred twelve".