31121200120 has 64 divisors (see below), whose sum is σ = 71855514720. Its totient is φ = 12124299264.

The previous prime is 31121200109. The next prime is 31121200133. The reversal of 31121200120 is 2100212113.

It is a self number, because there is not a number n which added to its sum of digits gives 31121200120.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 581532 + ... + 632788.

Almost surely, 2^31121200120 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 31121200120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35927757360).

31121200120 is an abundant number, since it is smaller than the sum of its proper divisors (40734314600).

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

31121200120 is a wasteful number, since it uses less digits than its factorization.

31121200120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51664 (or 51660 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 31121200120 its reverse (2100212113), we get a palindrome (33221412233).

The spelling of 31121200120 in words is "thirty-one billion, one hundred twenty-one million, two hundred thousand, one hundred twenty".