21002222022209 has 2 divisors, whose sum is σ = 21002222022210. Its totient is φ = 21002222022208.

The previous prime is 21002222022179. The next prime is 21002222022217. The reversal of 21002222022209 is 90222022220012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20172898530625 + 829323491584 = 4491425^2 + 910672^2 .

It is a cyclic number.

It is not a de Polignac number, because 21002222022209 - 2²⁰ = 21002220973633 is a prime.

It is not a weakly prime, because it can be changed into another prime (21002222022259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10501111011104 + 10501111011105.

It is an arithmetic number, because the mean of its divisors is an integer number (10501111011105).

Almost surely, 2^{21002222022209} is an apocalyptic number.

It is an amenable number.

21002222022209 is a deficient number, since it is larger than the sum of its proper divisors (1).

21002222022209 is an equidigital number, since it uses as much as digits as its factorization.

21002222022209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 26.

The spelling of 21002222022209 in words is "twenty-one trillion, two billion, two hundred twenty-two million, twenty-two thousand, two hundred nine".