21020122111211 has 2 divisors, whose sum is σ = 21020122111212. Its totient is φ = 21020122111210.

The previous prime is 21020122111187. The next prime is 21020122111361. The reversal of 21020122111211 is 11211122102012.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21020122111211 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21020122111211.

It is not a weakly prime, because it can be changed into another prime (21020122111511) 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, 10510061055605 + 10510061055606.

It is an arithmetic number, because the mean of its divisors is an integer number (10510061055606).

Almost surely, 2^{21020122111211} is an apocalyptic number.

21020122111211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020122111211 is an equidigital number, since it uses as much as digits as its factorization.

21020122111211 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21020122111211 its reverse (11211122102012), we get a palindrome (32231244213223).

The spelling of 21020122111211 in words is "twenty-one trillion, twenty billion, one hundred twenty-two million, one hundred eleven thousand, two hundred eleven".