22121002121221 has 2 divisors, whose sum is σ = 22121002121222. Its totient is φ = 22121002121220.

The previous prime is 22121002121161. The next prime is 22121002121233. The reversal of 22121002121221 is 12212120012122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18629668764100 + 3491333357121 = 4316210^2 + 1868511^2 .

It is a cyclic number.

It is not a de Polignac number, because 22121002121221 - 2¹⁵ = 22121002088453 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22121002121291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11060501060610 + 11060501060611.

It is an arithmetic number, because the mean of its divisors is an integer number (11060501060611).

Almost surely, 2^{22121002121221} is an apocalyptic number.

It is an amenable number.

22121002121221 is a deficient number, since it is larger than the sum of its proper divisors (1).

22121002121221 is an equidigital number, since it uses as much as digits as its factorization.

22121002121221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 22121002121221 its reverse (12212120012122), we get a palindrome (34333122133343).

The spelling of 22121002121221 in words is "twenty-two trillion, one hundred twenty-one billion, two million, one hundred twenty-one thousand, two hundred twenty-one".