21222120111066 has 64 divisors (see below), whose sum is σ = 54003337286400. Its totient is φ = 6051550333248.

The previous prime is 21222120111029. The next prime is 21222120111067. The reversal of 21222120111066 is 66011102122212.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21222120111067) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 54958065 + ... + 55342868.

It is an arithmetic number, because the mean of its divisors is an integer number (843802145100).

Almost surely, 2^{21222120111066} is an apocalyptic number.

21222120111066 is an abundant number, since it is smaller than the sum of its proper divisors (32781217175334).

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

21222120111066 is a wasteful number, since it uses less digits than its factorization.

21222120111066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110301460 (or 110301454 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

Adding to 21222120111066 its reverse (66011102122212), we get a palindrome (87233222233278).

The spelling of 21222120111066 in words is "twenty-one trillion, two hundred twenty-two billion, one hundred twenty million, one hundred eleven thousand, sixty-six".