21033122111 has 2 divisors, whose sum is σ = 21033122112. Its totient is φ = 21033122110.

The previous prime is 21033122081. The next prime is 21033122129. The reversal of 21033122111 is 11122133012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21033122111 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21033122111.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21033122161) 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, 10516561055 + 10516561056.

It is an arithmetic number, because the mean of its divisors is an integer number (10516561056).

Almost surely, 2^21033122111 is an apocalyptic number.

21033122111 is a deficient number, since it is larger than the sum of its proper divisors (1).

21033122111 is an equidigital number, since it uses as much as digits as its factorization.

21033122111 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21033122111 its reverse (11122133012), we get a palindrome (32155255123).

The spelling of 21033122111 in words is "twenty-one billion, thirty-three million, one hundred twenty-two thousand, one hundred eleven".