31989668 has 12 divisors (see below), whose sum is σ = 57912540. Its totient is φ = 15443232.

The previous prime is 31989667. The next prime is 31989677. The reversal of 31989668 is 86698913.

It can be written as a sum of positive squares in 2 ways, for example, as 10903204 + 21086464 = 3302^2 + 4592^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31989667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 137771 + ... + 138002.

It is an arithmetic number, because the mean of its divisors is an integer number (4826045).

Almost surely, 2^31989668 is an apocalyptic number.

It is an amenable number.

31989668 is a deficient number, since it is larger than the sum of its proper divisors (25922872).

31989668 is a wasteful number, since it uses less digits than its factorization.

31989668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 275806 (or 275804 counting only the distinct ones).

The product of its digits is 559872, while the sum is 50.

The square root of 31989668 is about 5655.9409473579. The cubic root of 31989668 is about 317.4460379079.

The spelling of 31989668 in words is "thirty-one million, nine hundred eighty-nine thousand, six hundred sixty-eight".