31991248 has 20 divisors (see below), whose sum is σ = 62460288. Its totient is φ = 15872480.

The previous prime is 31991237. The next prime is 31991249. The reversal of 31991248 is 84219913.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31991249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5536 + ... + 9727.

Almost surely, 2^31991248 is an apocalyptic number.

It is an amenable number.

31991248 is a deficient number, since it is larger than the sum of its proper divisors (30469040).

31991248 is a wasteful number, since it uses less digits than its factorization.

31991248 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15402 (or 15396 counting only the distinct ones).

The product of its digits is 15552, while the sum is 37.

The square root of 31991248 is about 5656.0806217733. The cubic root of 31991248 is about 317.4512641420.

The spelling of 31991248 in words is "thirty-one million, nine hundred ninety-one thousand, two hundred forty-eight".