31311220000 has 60 divisors (see below), whose sum is σ = 77030347086. Its totient is φ = 12524480000.

The previous prime is 31311219977. The next prime is 31311220009. The reversal of 31311220000 is 2211313.

It can be written as a sum of positive squares in 5 ways, for example, as 429484176 + 30881735824 = 20724^2 + 175732^2 .

It is not an unprimeable number, because it can be changed into a prime (31311220009) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 762781 + ... + 802780.

Almost surely, 2^31311220000 is an apocalyptic number.

It is an amenable number.

31311220000 is an abundant number, since it is smaller than the sum of its proper divisors (45719127086).

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

31311220000 is an equidigital number, since it uses as much as digits as its factorization.

31311220000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1565591 (or 1565568 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 13.

Adding to 31311220000 its reverse (2211313), we get a palindrome (31313431313).

The spelling of 31311220000 in words is "thirty-one billion, three hundred eleven million, two hundred twenty thousand".