21021122120 has 64 divisors (see below), whose sum is σ = 48951475200. Its totient is φ = 8114686720.

The previous prime is 21021122071. The next prime is 21021122137. The reversal of 21021122120 is 2122112012.

It is a junction number, because it is equal to n+sod(n) for n = 21021122095 and 21021122104.

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, 4785125 + ... + 4789515.

It is an arithmetic number, because the mean of its divisors is an integer number (764866800).

Almost surely, 2^21021122120 is an apocalyptic number.

21021122120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21021122120 is an abundant number, since it is smaller than the sum of its proper divisors (27930353080).

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

21021122120 is a wasteful number, since it uses less digits than its factorization.

21021122120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8558 (or 8554 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21021122120 its reverse (2122112012), we get a palindrome (23143234132).

The spelling of 21021122120 in words is "twenty-one billion, twenty-one million, one hundred twenty-two thousand, one hundred twenty".