21112111102111 has 4 divisors (see below), whose sum is σ = 21112216961272. Its totient is φ = 21112005242952.

The previous prime is 21112111102109. The next prime is 21112111102141. The reversal of 21112111102111 is 11120111121112.

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 21112111102111 - 2¹ = 21112111102109 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 (21112111102141) 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, 52629861 + ... + 53029486.

It is an arithmetic number, because the mean of its divisors is an integer number (5278054240318).

Almost surely, 2^{21112111102111} is an apocalyptic number.

21112111102111 is a deficient number, since it is larger than the sum of its proper divisors (105859161).

21112111102111 is a wasteful number, since it uses less digits than its factorization.

21112111102111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105859160.

The product of its (nonzero) digits is 8, while the sum is 16.

Adding to 21112111102111 its reverse (11120111121112), we get a palindrome (32232222223223).

The spelling of 21112111102111 in words is "twenty-one trillion, one hundred twelve billion, one hundred eleven million, one hundred two thousand, one hundred eleven".