21011211001211 has 2 divisors, whose sum is σ = 21011211001212. Its totient is φ = 21011211001210.

The previous prime is 21011211001189. The next prime is 21011211001217. The reversal of 21011211001211 is 11210011211012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21011211001211 - 2²² = 21011206806907 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (21011211001217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505605500605 + 10505605500606.

It is an arithmetic number, because the mean of its divisors is an integer number (10505605500606).

Almost surely, 2^{21011211001211} is an apocalyptic number.

21011211001211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21011211001211 is an equidigital number, since it uses as much as digits as its factorization.

21011211001211 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 21011211001211 its reverse (11210011211012), we get a palindrome (32221222212223).

The spelling of 21011211001211 in words is "twenty-one trillion, eleven billion, two hundred eleven million, one thousand, two hundred eleven".