31921420 has 12 divisors (see below), whose sum is σ = 67035024. Its totient is φ = 12768560.

The previous prime is 31921403. The next prime is 31921453. The reversal of 31921420 is 2412913.

It is a junction number, because it is equal to n+sod(n) for n = 31921391 and 31921400.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 798016 + ... + 798055.

It is an arithmetic number, because the mean of its divisors is an integer number (5586252).

Almost surely, 2^31921420 is an apocalyptic number.

It is an amenable number.

31921420 is an abundant number, since it is smaller than the sum of its proper divisors (35113604).

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

31921420 is a wasteful number, since it uses less digits than its factorization.

31921420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1596080 (or 1596078 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 31921420 is about 5649.9044239704. The cubic root of 31921420 is about 317.2201266074.

The spelling of 31921420 in words is "thirty-one million, nine hundred twenty-one thousand, four hundred twenty".