22021131221 has 2 divisors, whose sum is σ = 22021131222. Its totient is φ = 22021131220.

The previous prime is 22021131217. The next prime is 22021131227. The reversal of 22021131221 is 12213112022.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11260180996 + 10760950225 = 106114^2 + 103735^2 .

It is a cyclic number.

It is not a de Polignac number, because 22021131221 - 2² = 22021131217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 22021131221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22021131227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11010565610 + 11010565611.

It is an arithmetic number, because the mean of its divisors is an integer number (11010565611).

Almost surely, 2^22021131221 is an apocalyptic number.

It is an amenable number.

22021131221 is a deficient number, since it is larger than the sum of its proper divisors (1).

22021131221 is an equidigital number, since it uses as much as digits as its factorization.

22021131221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 22021131221 its reverse (12213112022), we get a palindrome (34234243243).

The spelling of 22021131221 in words is "twenty-two billion, twenty-one million, one hundred thirty-one thousand, two hundred twenty-one".