31331231320 has 32 divisors (see below), whose sum is σ = 70508128320. Its totient is φ = 12530206720.

The previous prime is 31331231263. The next prime is 31331231329. The reversal of 31331231320 is 2313213313.

It is a junction number, because it is equal to n+sod(n) for n = 31331231291 and 31331231300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31331231329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 159864 + ... + 297016.

It is an arithmetic number, because the mean of its divisors is an integer number (2203379010).

Almost surely, 2^31331231320 is an apocalyptic number.

It is an amenable number.

31331231320 is an abundant number, since it is smaller than the sum of its proper divisors (39176897000).

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

31331231320 is a wasteful number, since it uses less digits than its factorization.

31331231320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142875 (or 142871 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 22.

Adding to 31331231320 its reverse (2313213313), we get a palindrome (33644444633).

The spelling of 31331231320 in words is "thirty-one billion, three hundred thirty-one million, two hundred thirty-one thousand, three hundred twenty".