21001120022209 has 2 divisors, whose sum is σ = 21001120022210. Its totient is φ = 21001120022208.

The previous prime is 21001120022167. The next prime is 21001120022249. The reversal of 21001120022209 is 90222002110012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16651092330625 + 4350027691584 = 4080575^2 + 2085672^2 .

It is a cyclic number.

It is not a de Polignac number, because 21001120022209 - 2²¹ = 21001117925057 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21001120022209.

It is not a weakly prime, because it can be changed into another prime (21001120022249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500560011104 + 10500560011105.

It is an arithmetic number, because the mean of its divisors is an integer number (10500560011105).

Almost surely, 2^{21001120022209} is an apocalyptic number.

It is an amenable number.

21001120022209 is a deficient number, since it is larger than the sum of its proper divisors (1).

21001120022209 is an equidigital number, since it uses as much as digits as its factorization.

21001120022209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 22.

The spelling of 21001120022209 in words is "twenty-one trillion, one billion, one hundred twenty million, twenty-two thousand, two hundred nine".