21211444211 has 2 divisors, whose sum is σ = 21211444212. Its totient is φ = 21211444210.

The previous prime is 21211444207. The next prime is 21211444223. The reversal of 21211444211 is 11244411212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21211444211 - 2² = 21211444207 is a prime.

It is not a weakly prime, because it can be changed into another prime (21211444411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605722105 + 10605722106.

It is an arithmetic number, because the mean of its divisors is an integer number (10605722106).

Almost surely, 2^21211444211 is an apocalyptic number.

21211444211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211444211 is an equidigital number, since it uses as much as digits as its factorization.

21211444211 is an evil number, because the sum of its binary digits is even.

The product of its digits is 512, while the sum is 23.

Adding to 21211444211 its reverse (11244411212), we get a palindrome (32455855423).

The spelling of 21211444211 in words is "twenty-one billion, two hundred eleven million, four hundred forty-four thousand, two hundred eleven".