21100000111 has 16 divisors (see below), whose sum is σ = 22011264000. Its totient is φ = 20211373728.

The previous prime is 21100000069. The next prime is 21100000123. The reversal of 21100000111 is 11100000112.

It is a cyclic number.

It is not a de Polignac number, because 21100000111 - 2⁷ = 21099999983 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21100000094 and 21100000103.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100000151) 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, 485310 + ... + 526996.

It is an arithmetic number, because the mean of its divisors is an integer number (1375704000).

Almost surely, 2^21100000111 is an apocalyptic number.

21100000111 is a deficient number, since it is larger than the sum of its proper divisors (911263889).

21100000111 is a wasteful number, since it uses less digits than its factorization.

21100000111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41958.

The product of its (nonzero) digits is 2, while the sum is 7.

Adding to 21100000111 its reverse (11100000112), we get a palindrome (32200000223).

Subtracting from 21100000111 its reverse (11100000112), we obtain a palindrome (9999999999).

The spelling of 21100000111 in words is "twenty-one billion, one hundred million, one hundred eleven", and thus it is an aban number.