21202100111 has 16 divisors (see below), whose sum is σ = 22041331200. Its totient is φ = 20379720768.

The previous prime is 21202100099. The next prime is 21202100123. The reversal of 21202100111 is 11100120212.

It is an interprime number because it is at equal distance from previous prime (21202100099) and next prime (21202100123).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21202100111 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21202100092 and 21202100101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21202100141) 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, 3488171 + ... + 3494243.

It is an arithmetic number, because the mean of its divisors is an integer number (1377583200).

Almost surely, 2^21202100111 is an apocalyptic number.

21202100111 is a deficient number, since it is larger than the sum of its proper divisors (839231089).

21202100111 is a wasteful number, since it uses less digits than its factorization.

21202100111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7438.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21202100111 its reverse (11100120212), we get a palindrome (32302220323).

The spelling of 21202100111 in words is "twenty-one billion, two hundred two million, one hundred thousand, one hundred eleven".