21202210002221 has 2 divisors, whose sum is σ = 21202210002222. Its totient is φ = 21202210002220.

The previous prime is 21202210002187. The next prime is 21202210002251. The reversal of 21202210002221 is 12220001220212.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11665298702500 + 9536911299721 = 3415450^2 + 3088189^2 .

It is a cyclic number.

It is not a de Polignac number, because 21202210002221 - 2²² = 21202205807917 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21202210002221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21202210002251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10601105001110 + 10601105001111.

It is an arithmetic number, because the mean of its divisors is an integer number (10601105001111).

Almost surely, 2^{21202210002221} is an apocalyptic number.

It is an amenable number.

21202210002221 is a deficient number, since it is larger than the sum of its proper divisors (1).

21202210002221 is an equidigital number, since it uses as much as digits as its factorization.

21202210002221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21202210002221 its reverse (12220001220212), we get a palindrome (33422211222433).

The spelling of 21202210002221 in words is "twenty-one trillion, two hundred two billion, two hundred ten million, two thousand, two hundred twenty-one".