31113120220 has 96 divisors (see below), whose sum is σ = 80673844608. Its totient is φ = 9815150592.

The previous prime is 31113120193. The next prime is 31113120221. The reversal of 31113120220 is 2202131113.

It is a junction number, because it is equal to n+sod(n) for n = 31113120194 and 31113120203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31113120221) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 542352 + ... + 596968.

It is an arithmetic number, because the mean of its divisors is an integer number (840352548).

Almost surely, 2^31113120220 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31113120220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40336922304).

31113120220 is an abundant number, since it is smaller than the sum of its proper divisors (49560724388).

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

31113120220 is a wasteful number, since it uses less digits than its factorization.

31113120220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54959 (or 54957 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 31113120220 its reverse (2202131113), we get a palindrome (33315251333).

The spelling of 31113120220 in words is "thirty-one billion, one hundred thirteen million, one hundred twenty thousand, two hundred twenty".