21121121122320 has 160 divisors (see below), whose sum is σ = 65914571197440. Its totient is φ = 5594533516800.

The previous prime is 21121121122301. The next prime is 21121121122331. The reversal of 21121121122320 is 2322112112112.

It is a super-2 number, since 2×21121121122320² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 798245251 + ... + 798271709.

It is an arithmetic number, because the mean of its divisors is an integer number (411966069984).

Almost surely, 2^{21121121122320} is an apocalyptic number.

21121121122320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21121121122320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32957285598720).

21121121122320 is an abundant number, since it is smaller than the sum of its proper divisors (44793450075120).

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

21121121122320 is a wasteful number, since it uses less digits than its factorization.

21121121122320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48653 (or 48647 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 21.

Adding to 21121121122320 its reverse (2322112112112), we get a palindrome (23443233234432).

The spelling of 21121121122320 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred twenty-one million, one hundred twenty-two thousand, three hundred twenty".