31311332120 has 16 divisors (see below), whose sum is σ = 70450497360. Its totient is φ = 12524532832.

The previous prime is 31311332119. The next prime is 31311332123. The reversal of 31311332120 is 2123311313.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 31311332092 and 31311332101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31311332123) 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, 391391612 + ... + 391391691.

It is an arithmetic number, because the mean of its divisors is an integer number (4403156085).

Almost surely, 2^31311332120 is an apocalyptic number.

It is an amenable number.

31311332120 is an abundant number, since it is smaller than the sum of its proper divisors (39139165240).

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

31311332120 is a wasteful number, since it uses less digits than its factorization.

31311332120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 782783314 (or 782783310 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 20.

Adding to 31311332120 its reverse (2123311313), we get a palindrome (33434643433).

The spelling of 31311332120 in words is "thirty-one billion, three hundred eleven million, three hundred thirty-two thousand, one hundred twenty".