31999843225 has 81 divisors (see below), whose sum is σ = 48897150237. Its totient is φ = 20710589760.

The previous prime is 31999843181. The next prime is 31999843229. The reversal of 31999843225 is 52234899913.

The square root of 31999843225 is 178885.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 12274202521 + 19725640704 = 110789^2 + 140448^2 .

It is not a de Polignac number, because 31999843225 - 2⁷ = 31999843097 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31999843229) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 118958391 + ... + 118958659.

Almost surely, 2^31999843225 is an apocalyptic number.

31999843225 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

31999843225 is the 178885-th square number.

31999843225 is the 89443-rd centered octagonal number.

It is an amenable number.

31999843225 is a deficient number, since it is larger than the sum of its proper divisors (16897307012).

31999843225 is an equidigital number, since it uses as much as digits as its factorization.

31999843225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 600 (or 300 counting only the distinct ones).

The product of its digits is 4199040, while the sum is 55.

The spelling of 31999843225 in words is "thirty-one billion, nine hundred ninety-nine million, eight hundred forty-three thousand, two hundred twenty-five".