222221991221 has 2 divisors, whose sum is σ = 222221991222. Its totient is φ = 222221991220.

The previous prime is 222221991217. The next prime is 222221991253. The reversal of 222221991221 is 122199122222.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 167109264100 + 55112727121 = 408790^2 + 234761^2 .

It is a cyclic number.

It is not a de Polignac number, because 222221991221 - 2² = 222221991217 is a prime.

It is a super-2 number, since 2×222221991221² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (222221991521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 111110995610 + 111110995611.

It is an arithmetic number, because the mean of its divisors is an integer number (111110995611).

Almost surely, 2^222221991221 is an apocalyptic number.

It is an amenable number.

222221991221 is a deficient number, since it is larger than the sum of its proper divisors (1).

222221991221 is an equidigital number, since it uses as much as digits as its factorization.

222221991221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10368, while the sum is 35.

The spelling of 222221991221 in words is "two hundred twenty-two billion, two hundred twenty-one million, nine hundred ninety-one thousand, two hundred twenty-one".