31231120311220 has 48 divisors (see below), whose sum is σ = 68439028428288. Its totient is φ = 11948924782080.

The previous prime is 31231120311191. The next prime is 31231120311221. The reversal of 31231120311220 is 2211302113213.

It is a junction number, because it is equal to n+sod(n) for n = 31231120311191 and 31231120311200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31231120311221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13904005 + ... + 15993235.

It is an arithmetic number, because the mean of its divisors is an integer number (1425813092256).

Almost surely, 2^{31231120311220} is an apocalyptic number.

It is an amenable number.

31231120311220 is an abundant number, since it is smaller than the sum of its proper divisors (37207908117068).

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

31231120311220 is a wasteful number, since it uses less digits than its factorization.

31231120311220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2121760 (or 2121758 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 22.

Adding to 31231120311220 its reverse (2211302113213), we get a palindrome (33442422424433).

The spelling of 31231120311220 in words is "thirty-one trillion, two hundred thirty-one billion, one hundred twenty million, three hundred eleven thousand, two hundred twenty".