31989136 has 20 divisors (see below), whose sum is σ = 64674432. Its totient is φ = 15298976.

The previous prime is 31989101. The next prime is 31989137. The reversal of 31989136 is 63198913.

It is not an unprimeable number, because it can be changed into a prime (31989137) 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, 43096 + ... + 43831.

Almost surely, 2^31989136 is an apocalyptic number.

It is an amenable number.

31989136 is an abundant number, since it is smaller than the sum of its proper divisors (32685296).

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

31989136 is a wasteful number, since it uses less digits than its factorization.

31989136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86958 (or 86952 counting only the distinct ones).

The product of its digits is 34992, while the sum is 40.

The square root of 31989136 is about 5655.8939169684. The cubic root of 31989136 is about 317.4442781499. Note that the first 3 decimals are identical.

The spelling of 31989136 in words is "thirty-one million, nine hundred eighty-nine thousand, one hundred thirty-six".