22121221220 has 48 divisors (see below), whose sum is σ = 53105165568. Its totient is φ = 7582385280.

The previous prime is 22121221217. The next prime is 22121221223. The reversal of 22121221220 is 2212212122.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (22121221217) and next prime (22121221223).

It is not an unprimeable number, because it can be changed into a prime (22121221223) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 559505 + ... + 597735.

It is an arithmetic number, because the mean of its divisors is an integer number (1106357616).

Almost surely, 2^22121221220 is an apocalyptic number.

22121221220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22121221220 is an abundant number, since it is smaller than the sum of its proper divisors (30983944348).

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

22121221220 is a wasteful number, since it uses less digits than its factorization.

22121221220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42380 (or 42378 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 22121221220 its reverse (2212212122), we get a palindrome (24333433342).

The spelling of 22121221220 in words is "twenty-two billion, one hundred twenty-one million, two hundred twenty-one thousand, two hundred twenty".