222120111021221 has 6 divisors (see below), whose sum is σ = 258384618943110. Its totient is φ = 190388666589576.

The previous prime is 222120111021203. The next prime is 222120111021269. The reversal of 222120111021221 is 122120111021222.

It can be written as a sum of positive squares in only one way, i.e., 215678184792196 + 6441926229025 = 14685986^2 + 2538095^2 .

It is not a de Polignac number, because 222120111021221 - 2¹⁴ = 222120111004837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 222120111021193 and 222120111021202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222120111021271) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2266531745066 + ... + 2266531745163.

It is an arithmetic number, because the mean of its divisors is an integer number (43064103157185).

Almost surely, 2^{222120111021221} is an apocalyptic number.

It is an amenable number.

222120111021221 is a deficient number, since it is larger than the sum of its proper divisors (36264507921889).

222120111021221 is an equidigital number, since it uses as much as digits as its factorization.

222120111021221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4533063490243 (or 4533063490236 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 222120111021221 its reverse (122120111021222), we get a palindrome (344240222042443).

Subtracting from 222120111021221 its reverse (122120111021222), we obtain a palindrome (99999999999999).

It can be divided in two parts, 22212011 and 1021221, that added together give a palindrome (23233232).

The spelling of 222120111021221 in words is "two hundred twenty-two trillion, one hundred twenty billion, one hundred eleven million, twenty-one thousand, two hundred twenty-one".