31313325220 has 24 divisors (see below), whose sum is σ = 65927043000. Its totient is φ = 12493128192.

The previous prime is 31313325209. The next prime is 31313325233. The reversal of 31313325220 is 2252331313.

It can be written as a sum of positive squares in 4 ways, for example, as 378847296 + 30934477924 = 19464^2 + 175882^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2004645 + ... + 2020204.

It is an arithmetic number, because the mean of its divisors is an integer number (2746960125).

Almost surely, 2^31313325220 is an apocalyptic number.

It is an amenable number.

31313325220 is an abundant number, since it is smaller than the sum of its proper divisors (34613717780).

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

31313325220 is a wasteful number, since it uses less digits than its factorization.

31313325220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4025247 (or 4025245 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 25.

Adding to 31313325220 its reverse (2252331313), we get a palindrome (33565656533).

The spelling of 31313325220 in words is "thirty-one billion, three hundred thirteen million, three hundred twenty-five thousand, two hundred twenty".