22222212121 has 2 divisors, whose sum is σ = 22222212122. Its totient is φ = 22222212120.

The previous prime is 22222212119. The next prime is 22222212127. The reversal of 22222212121 is 12121222222.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18581779225 + 3640432896 = 136315^2 + 60336^2 .

It is a cyclic number.

It is not a de Polignac number, because 22222212121 - 2¹ = 22222212119 is a prime.

Together with 22222212119, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (22222212127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11111106060 + 11111106061.

It is an arithmetic number, because the mean of its divisors is an integer number (11111106061).

Almost surely, 2^22222212121 is an apocalyptic number.

It is an amenable number.

22222212121 is a deficient number, since it is larger than the sum of its proper divisors (1).

22222212121 is an equidigital number, since it uses as much as digits as its factorization.

22222212121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 256, while the sum is 19.

Adding to 22222212121 its reverse (12121222222), we get a palindrome (34343434343).

The spelling of 22222212121 in words is "twenty-two billion, two hundred twenty-two million, two hundred twelve thousand, one hundred twenty-one".