31686864 has 40 divisors (see below), whose sum is σ = 89300832. Its totient is φ = 9601920.

The previous prime is 31686841. The next prime is 31686869. The reversal of 31686864 is 46868613.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31686869) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29479 + ... + 30534.

Almost surely, 2^31686864 is an apocalyptic number.

It is an amenable number.

31686864 is an abundant number, since it is smaller than the sum of its proper divisors (57613968).

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

31686864 is a wasteful number, since it uses less digits than its factorization.

31686864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60035 (or 60029 counting only the distinct ones).

The product of its digits is 165888, while the sum is 42.

The square root of 31686864 is about 5629.1086328121. The cubic root of 31686864 is about 316.4412465280.

The spelling of 31686864 in words is "thirty-one million, six hundred eighty-six thousand, eight hundred sixty-four".