31129872 has 40 divisors (see below), whose sum is σ = 80801376. Its totient is φ = 10327296.

The previous prime is 31129867. The next prime is 31129877. The reversal of 31129872 is 27892113.

It is an interprime number because it is at equal distance from previous prime (31129867) and next prime (31129877).

It is not an unprimeable number, because it can be changed into a prime (31129877) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9468 + ... + 12324.

Almost surely, 2^31129872 is an apocalyptic number.

It is an amenable number.

31129872 is an abundant number, since it is smaller than the sum of its proper divisors (49671504).

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

31129872 is a wasteful number, since it uses less digits than its factorization.

31129872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3095 (or 3089 counting only the distinct ones).

The product of its digits is 6048, while the sum is 33.

The square root of 31129872 is about 5579.4150231005. The cubic root of 31129872 is about 314.5761394122.

The spelling of 31129872 in words is "thirty-one million, one hundred twenty-nine thousand, eight hundred seventy-two".