21210222211 has 2 divisors, whose sum is σ = 21210222212. Its totient is φ = 21210222210.

The previous prime is 21210222157. The next prime is 21210222259. The reversal of 21210222211 is 11222201212.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21210222211 - 2⁹ = 21210221699 is a prime.

It is not a weakly prime, because it can be changed into another prime (21210220211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605111105 + 10605111106.

It is an arithmetic number, because the mean of its divisors is an integer number (10605111106).

Almost surely, 2^21210222211 is an apocalyptic number.

21210222211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21210222211 is an equidigital number, since it uses as much as digits as its factorization.

21210222211 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21210222211 its reverse (11222201212), we get a palindrome (32432423423).

The spelling of 21210222211 in words is "twenty-one billion, two hundred ten million, two hundred twenty-two thousand, two hundred eleven".