31664 has 10 divisors (see below), whose sum is σ = 61380. Its totient is φ = 15824.

The previous prime is 31663. The next prime is 31667. The reversal of 31664 is 46613.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 31664.

It is not an unprimeable number, because it can be changed into a prime (31663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 974 + ... + 1005.

It is an arithmetic number, because the mean of its divisors is an integer number (6138).

2³¹⁶⁶⁴ is an apocalyptic number.

It is an amenable number.

31664 is a deficient number, since it is larger than the sum of its proper divisors (29716).

31664 is a wasteful number, since it uses less digits than its factorization.

31664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1987 (or 1981 counting only the distinct ones).

The product of its digits is 432, while the sum is 20.

The square root of 31664 is about 177.9438113563. The cubic root of 31664 is about 31.6365117678.

Adding to 31664 its sum of digits (20), we get a square (31684 = 178²).

The spelling of 31664 in words is "thirty-one thousand, six hundred sixty-four".