22121110220021 has 2 divisors, whose sum is σ = 22121110220022. Its totient is φ = 22121110220020.

The previous prime is 22121110219997. The next prime is 22121110220023. The reversal of 22121110220021 is 12002201112122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21182315880625 + 938794339396 = 4602425^2 + 968914^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22121110220021 is a prime.

Together with 22121110220023, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22121110220023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11060555110010 + 11060555110011.

It is an arithmetic number, because the mean of its divisors is an integer number (11060555110011).

Almost surely, 2^{22121110220021} is an apocalyptic number.

It is an amenable number.

22121110220021 is a deficient number, since it is larger than the sum of its proper divisors (1).

22121110220021 is an equidigital number, since it uses as much as digits as its factorization.

22121110220021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 22121110220021 its reverse (12002201112122), we get a palindrome (34123311332143).

The spelling of 22121110220021 in words is "twenty-two trillion, one hundred twenty-one billion, one hundred ten million, two hundred twenty thousand, twenty-one".