21122012222220 has 192 divisors, whose sum is σ = 72857815188480. Its totient is φ = 4452342377472.

The previous prime is 21122012222173. The next prime is 21122012222279. The reversal of 21122012222220 is 2222221022112.

It is a super-2 number, since 2×21122012222220² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4027339 + ... + 7646141.

It is an arithmetic number, because the mean of its divisors is an integer number (379467787440).

Almost surely, 2^{21122012222220} is an apocalyptic number.

21122012222220 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 21122012222220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36428907594240).

21122012222220 is an abundant number, since it is smaller than the sum of its proper divisors (51735802966260).

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

21122012222220 is a wasteful number, since it uses less digits than its factorization.

21122012222220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3619904 (or 3619902 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 21.

Adding to 21122012222220 its reverse (2222221022112), we get a palindrome (23344233244332).

The spelling of 21122012222220 in words is "twenty-one trillion, one hundred twenty-two billion, twelve million, two hundred twenty-two thousand, two hundred twenty".