21011230211 has 2 divisors, whose sum is σ = 21011230212. Its totient is φ = 21011230210.

The previous prime is 21011230193. The next prime is 21011230243. The reversal of 21011230211 is 11203211012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21011230211 - 2⁶ = 21011230147 is a prime.

It is not a weakly prime, because it can be changed into another prime (21011230711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505615105 + 10505615106.

It is an arithmetic number, because the mean of its divisors is an integer number (10505615106).

Almost surely, 2^21011230211 is an apocalyptic number.

21011230211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21011230211 is an equidigital number, since it uses as much as digits as its factorization.

21011230211 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 21011230211 its reverse (11203211012), we get a palindrome (32214441223).

The spelling of 21011230211 in words is "twenty-one billion, eleven million, two hundred thirty thousand, two hundred eleven".