21122012911 has 2 divisors, whose sum is σ = 21122012912. Its totient is φ = 21122012910.

The previous prime is 21122012909. The next prime is 21122013007. The reversal of 21122012911 is 11921022112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21122012911 - 2¹ = 21122012909 is a prime.

It is a super-2 number, since 2×21122012911² (a number of 21 digits) contains 22 as substring.

Together with 21122012909, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21122010911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10561006455 + 10561006456.

It is an arithmetic number, because the mean of its divisors is an integer number (10561006456).

Almost surely, 2^21122012911 is an apocalyptic number.

21122012911 is a deficient number, since it is larger than the sum of its proper divisors (1).

21122012911 is an equidigital number, since it uses as much as digits as its factorization.

21122012911 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 22.

It can be divided in two parts, 2112201 and 2911, that added together give a palindrome (2115112).

The spelling of 21122012911 in words is "twenty-one billion, one hundred twenty-two million, twelve thousand, nine hundred eleven".