31991999488 has 44 divisors (see below), whose sum is σ = 65001289552. Its totient is φ = 15733739520.

The previous prime is 31991999483. The next prime is 31991999489. The reversal of 31991999488 is 88499919913.

It is not an unprimeable number, because it can be changed into a prime (31991999483) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 193620 + ... + 318547.

Almost surely, 2^31991999488 is an apocalyptic number.

It is an amenable number.

31991999488 is an abundant number, since it is smaller than the sum of its proper divisors (33009290064).

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

31991999488 is an equidigital number, since it uses as much as digits as its factorization.

31991999488 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 512248 (or 512230 counting only the distinct ones).

The product of its digits is 45349632, while the sum is 70.

The spelling of 31991999488 in words is "thirty-one billion, nine hundred ninety-one million, nine hundred ninety-nine thousand, four hundred eighty-eight".