21120111102111 has 16 divisors (see below), whose sum is σ = 32267055243264. Its totient is φ = 12037124114784.

The previous prime is 21120111101987. The next prime is 21120111102179. The reversal of 21120111102111 is 11120111102112.

It is not a de Polignac number, because 21120111102111 - 2⁷ = 21120111101983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120111122111) 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, 1312941796 + ... + 1312957881.

It is an arithmetic number, because the mean of its divisors is an integer number (2016690952704).

Almost surely, 2^{21120111102111} is an apocalyptic number.

21120111102111 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21120111102111 is a deficient number, since it is larger than the sum of its proper divisors (11146944141153).

21120111102111 is a wasteful number, since it uses less digits than its factorization.

21120111102111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2625900070.

The product of its (nonzero) digits is 8, while the sum is 15.

Adding to 21120111102111 its reverse (11120111102112), we get a palindrome (32240222204223).

Subtracting from 21120111102111 its reverse (11120111102112), we obtain a palindrome (9999999999999).

The spelling of 21120111102111 in words is "twenty-one trillion, one hundred twenty billion, one hundred eleven million, one hundred two thousand, one hundred eleven".