21444324222221 has 2 divisors, whose sum is σ = 21444324222222. Its totient is φ = 21444324222220.

The previous prime is 21444324222199. The next prime is 21444324222229. The reversal of 21444324222221 is 12222242344412.

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., 18426672316900 + 3017651905321 = 4292630^2 + 1737139^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21444324222221 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21444324222229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10722162111110 + 10722162111111.

It is an arithmetic number, because the mean of its divisors is an integer number (10722162111111).

Almost surely, 2^{21444324222221} is an apocalyptic number.

It is an amenable number.

21444324222221 is a deficient number, since it is larger than the sum of its proper divisors (1).

21444324222221 is an equidigital number, since it uses as much as digits as its factorization.

21444324222221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 98304, while the sum is 35.

Adding to 21444324222221 its reverse (12222242344412), we get a palindrome (33666566566633).

The spelling of 21444324222221 in words is "twenty-one trillion, four hundred forty-four billion, three hundred twenty-four million, two hundred twenty-two thousand, two hundred twenty-one".