21011100211 has 2 divisors, whose sum is σ = 21011100212. Its totient is φ = 21011100210.

The previous prime is 21011100079. The next prime is 21011100217. The reversal of 21011100211 is 11200111012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21011100211 - 2⁹ = 21011099699 is a prime.

It is not a weakly prime, because it can be changed into another prime (21011100217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505550105 + 10505550106.

It is an arithmetic number, because the mean of its divisors is an integer number (10505550106).

Almost surely, 2^21011100211 is an apocalyptic number.

21011100211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21011100211 is an equidigital number, since it uses as much as digits as its factorization.

21011100211 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 21011100211 its reverse (11200111012), we get a palindrome (32211211223).

The spelling of 21011100211 in words is "twenty-one billion, eleven million, one hundred thousand, two hundred eleven".