21110112111111 has 16 divisors (see below), whose sum is σ = 28936053378048. Its totient is φ = 13682755476000.

The previous prime is 21110112111091. The next prime is 21110112111149. The reversal of 21110112111111 is 11111121101112.

It is a happy number.

It is not a de Polignac number, because 21110112111111 - 2²⁹ = 21109575240199 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21110112111191) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 495730720 + ... + 495773301.

It is an arithmetic number, because the mean of its divisors is an integer number (1808503336128).

Almost surely, 2^{21110112111111} is an apocalyptic number.

21110112111111 is a deficient number, since it is larger than the sum of its proper divisors (7825941266937).

21110112111111 is a wasteful number, since it uses less digits than its factorization.

21110112111111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 991504222.

The product of its (nonzero) digits is 4, while the sum is 15.

Adding to 21110112111111 its reverse (11111121101112), we get a palindrome (32221233212223).

The spelling of 21110112111111 in words is "twenty-one trillion, one hundred ten billion, one hundred twelve million, one hundred eleven thousand, one hundred eleven".