31421856 has 24 divisors (see below), whose sum is σ = 82482624. Its totient is φ = 10473920.

The previous prime is 31421851. The next prime is 31421857. The reversal of 31421856 is 65812413.

It is a tau number, because it is divible by the number of its divisors (24).

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (31421851) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 163560 + ... + 163751.

It is an arithmetic number, because the mean of its divisors is an integer number (3436776).

Almost surely, 2^31421856 is an apocalyptic number.

It is an amenable number.

31421856 is an abundant number, since it is smaller than the sum of its proper divisors (51060768).

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

31421856 is a wasteful number, since it uses less digits than its factorization.

31421856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 327324 (or 327316 counting only the distinct ones).

The product of its digits is 5760, while the sum is 30.

The square root of 31421856 is about 5605.5201364369. The cubic root of 31421856 is about 315.5566072246.

The spelling of 31421856 in words is "thirty-one million, four hundred twenty-one thousand, eight hundred fifty-six".