22121221000000 has 392 divisors, whose sum is σ = 56342035062720. Its totient is φ = 8612620800000.

The previous prime is 22121220999991. The next prime is 22121221000003. The reversal of 22121221000000 is 12212122.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22121221000003) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 15436999284 + ... + 15437000716.

Almost surely, 2^{22121221000000} is an apocalyptic number.

22121221000000 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 22121221000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28171017531360).

22121221000000 is an abundant number, since it is smaller than the sum of its proper divisors (34220814062720).

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

22121221000000 is an frugal number, since it uses more digits than its factorization.

22121221000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1877 (or 1842 counting only the distinct ones).

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

Adding to 22121221000000 its reverse (12212122), we get a palindrome (22121233212122).

The spelling of 22121221000000 in words is "twenty-two trillion, one hundred twenty-one billion, two hundred twenty-one million", and thus it is an aban number.