21044440211 has 2 divisors, whose sum is σ = 21044440212. Its totient is φ = 21044440210.

The previous prime is 21044440187. The next prime is 21044440213. The reversal of 21044440211 is 11204444012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21044440211 - 2³⁴ = 3864571027 is a prime.

It is a Sophie Germain prime.

Together with 21044440213, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21044440213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10522220105 + 10522220106.

It is an arithmetic number, because the mean of its divisors is an integer number (10522220106).

Almost surely, 2^21044440211 is an apocalyptic number.

21044440211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21044440211 is an equidigital number, since it uses as much as digits as its factorization.

21044440211 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1024, while the sum is 23.

Adding to 21044440211 its reverse (11204444012), we get a palindrome (32248884223).

The spelling of 21044440211 in words is "twenty-one billion, forty-four million, four hundred forty thousand, two hundred eleven".