21222222111220 has 24 divisors (see below), whose sum is σ = 47994871544424. Its totient is φ = 7835897394816.

The previous prime is 21222222111193. The next prime is 21222222111227. The reversal of 21222222111220 is 2211122222212.

It can be written as a sum of positive squares in 4 ways, for example, as 1202360496484 + 20019861614736 = 1096522^2 + 4474356^2 .

It is a super-2 number, since 2×21222222111220² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21222222111191 and 21222222111200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222222111227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40811965339 + ... + 40811965858.

It is an arithmetic number, because the mean of its divisors is an integer number (1999786314351).

Almost surely, 2^{21222222111220} is an apocalyptic number.

21222222111220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21222222111220 is an abundant number, since it is smaller than the sum of its proper divisors (26772649433204).

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

21222222111220 is a wasteful number, since it uses less digits than its factorization.

21222222111220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81623931219 (or 81623931217 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 22.

Adding to 21222222111220 its reverse (2211122222212), we get a palindrome (23433344333432).

The spelling of 21222222111220 in words is "twenty-one trillion, two hundred twenty-two billion, two hundred twenty-two million, one hundred eleven thousand, two hundred twenty".