21111011110111 has 16 divisors (see below), whose sum is σ = 23120853073920. Its totient is φ = 19156316870880.

The previous prime is 21111011110093. The next prime is 21111011110139. The reversal of 21111011110111 is 11101111011112.

It is a cyclic number.

It is not a de Polignac number, because 21111011110111 - 2⁷ = 21111011109983 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21111011110091 and 21111011110100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21111011110171) 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, 32245026 + ... + 32893216.

It is an arithmetic number, because the mean of its divisors is an integer number (1445053317120).

Almost surely, 2^{21111011110111} is an apocalyptic number.

21111011110111 is a deficient number, since it is larger than the sum of its proper divisors (2009841963809).

21111011110111 is a wasteful number, since it uses less digits than its factorization.

21111011110111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 690726.

The product of its (nonzero) digits is 2, while the sum is 13.

Adding to 21111011110111 its reverse (11101111011112), we get a palindrome (32212122121223).

The spelling of 21111011110111 in words is "twenty-one trillion, one hundred eleven billion, eleven million, one hundred ten thousand, one hundred eleven".