21201111110 has 24 divisors (see below), whose sum is σ = 39432760848. Its totient is φ = 8206878000.

The previous prime is 21201111109. The next prime is 21201111131. The reversal of 21201111110 is 1111110212.

It is a super-2 number, since 2×21201111110² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21201111091 and 21201111100.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1093466 + ... + 1112685.

It is an arithmetic number, because the mean of its divisors is an integer number (1643031702).

Almost surely, 2^21201111110 is an apocalyptic number.

21201111110 is a deficient number, since it is larger than the sum of its proper divisors (18231649738).

21201111110 is a wasteful number, since it uses less digits than its factorization.

21201111110 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2206220 (or 2206189 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 11.

Adding to 21201111110 its reverse (1111110212), we get a palindrome (22312221322).

The spelling of 21201111110 in words is "twenty-one billion, two hundred one million, one hundred eleven thousand, one hundred ten".