222222121021 has 2 divisors, whose sum is σ = 222222121022. Its totient is φ = 222222121020.

The previous prime is 222222121013. The next prime is 222222121057. The reversal of 222222121021 is 120121222222.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 206979502500 + 15242618521 = 454950^2 + 123461^2 .

It is a cyclic number.

It is not a de Polignac number, because 222222121021 - 2³ = 222222121013 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 222222121021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (222222121081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 111111060510 + 111111060511.

It is an arithmetic number, because the mean of its divisors is an integer number (111111060511).

Almost surely, 2^222222121021 is an apocalyptic number.

It is an amenable number.

222222121021 is a deficient number, since it is larger than the sum of its proper divisors (1).

222222121021 is an equidigital number, since it uses as much as digits as its factorization.

222222121021 is an odious number, because the sum of its binary digits is odd.

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

Adding to 222222121021 its reverse (120121222222), we get a palindrome (342343343243).

The spelling of 222222121021 in words is "two hundred twenty-two billion, two hundred twenty-two million, one hundred twenty-one thousand, twenty-one".