21121101012220 has 360 divisors, whose sum is σ = 51877283843952. Its totient is φ = 7217608273920.

The previous prime is 21121101012191. The next prime is 21121101012289. The reversal of 21121101012220 is 2221010112112.

It is a super-2 number, since 2×21121101012220² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21121101012194 and 21121101012203.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 60867726087 + ... + 60867726433.

Almost surely, 2^{21121101012220} is an apocalyptic number.

21121101012220 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 21121101012220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25938641921976).

21121101012220 is an abundant number, since it is smaller than the sum of its proper divisors (30756182831732).

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

21121101012220 is a wasteful number, since it uses less digits than its factorization.

21121101012220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 647 (or 577 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21121101012220 its reverse (2221010112112), we get a palindrome (23342111124332).

The spelling of 21121101012220 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred one million, twelve thousand, two hundred twenty".