21102221200000 has 192 divisors, whose sum is σ = 54358078282200. Its totient is φ = 8149818880000.

The previous prime is 21102221199977. The next prime is 21102221200001. The reversal of 21102221200000 is 212220112.

It is a happy number.

It can be written as a sum of positive squares in 12 ways, for example, as 4685008302144 + 16417212897856 = 2164488^2 + 4051816^2 .

It is not an unprimeable number, because it can be changed into a prime (21102221200001) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10690422 + ... + 12509578.

Almost surely, 2^{21102221200000} is an apocalyptic number.

21102221200000 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 21102221200000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27179039141100).

21102221200000 is an abundant number, since it is smaller than the sum of its proper divisors (33255857082200).

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

21102221200000 is an frugal number, since it uses more digits than its factorization.

21102221200000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1819225 (or 1819193 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21102221200000 its reverse (212220112), we get a palindrome (21102433420112).

The spelling of 21102221200000 in words is "twenty-one trillion, one hundred two billion, two hundred twenty-one million, two hundred thousand".