21112102120111 has 4 divisors (see below), whose sum is σ = 21112139517912. Its totient is φ = 21112064722312.

The previous prime is 21112102120073. The next prime is 21112102120141. The reversal of 21112102120111 is 11102120121112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21112102120111 - 2²⁹ = 21111565249199 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112102120141) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17838925 + ... + 18985558.

It is an arithmetic number, because the mean of its divisors is an integer number (5278034879478).

Almost surely, 2^{21112102120111} is an apocalyptic number.

21112102120111 is a deficient number, since it is larger than the sum of its proper divisors (37397801).

21112102120111 is an equidigital number, since it uses as much as digits as its factorization.

21112102120111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37397800.

The product of its (nonzero) digits is 16, while the sum is 16.

Adding to 21112102120111 its reverse (11102120121112), we get a palindrome (32214222241223).

The spelling of 21112102120111 in words is "twenty-one trillion, one hundred twelve billion, one hundred two million, one hundred twenty thousand, one hundred eleven".