21100100111 has 8 divisors (see below), whose sum is σ = 22776720480. Its totient is φ = 19486748512.

The previous prime is 21100100093. The next prime is 21100100143. The reversal of 21100100111 is 11100100112.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21100100111 - 2¹⁰ = 21100099087 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 (21100100011) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15816500 + ... + 15817833.

It is an arithmetic number, because the mean of its divisors is an integer number (2847090060).

Almost surely, 2^21100100111 is an apocalyptic number.

21100100111 is a deficient number, since it is larger than the sum of its proper divisors (1676620369).

21100100111 is a wasteful number, since it uses less digits than its factorization.

21100100111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31634385.

The product of its (nonzero) digits is 2, while the sum is 8.

Adding to 21100100111 its reverse (11100100112), we get a palindrome (32200200223).

Subtracting from 21100100111 its reverse (11100100112), we obtain a palindrome (9999999999).

The spelling of 21100100111 in words is "twenty-one billion, one hundred million, one hundred thousand, one hundred eleven".