31315872 has 48 divisors (see below), whose sum is σ = 93949632. Its totient is φ = 8947200.

The previous prime is 31315861. The next prime is 31315877. The reversal of 31315872 is 27851313.

It is a tau number, because it is divible by the number of its divisors (48).

It is not an unprimeable number, because it can be changed into a prime (31315877) 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, 22629 + ... + 23972.

It is an arithmetic number, because the mean of its divisors is an integer number (1957284).

Almost surely, 2^31315872 is an apocalyptic number.

31315872 is a gapful number since it is divisible by the number (32) formed by its first and last digit.

It is an amenable number.

31315872 is an abundant number, since it is smaller than the sum of its proper divisors (62633760).

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

31315872 is a wasteful number, since it uses less digits than its factorization.

31315872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46621 (or 46613 counting only the distinct ones).

The product of its digits is 5040, while the sum is 30.

The square root of 31315872 is about 5596.0586129883. The cubic root of 31315872 is about 315.2014232030.

The spelling of 31315872 in words is "thirty-one million, three hundred fifteen thousand, eight hundred seventy-two".