21001111122110 has 64 divisors (see below), whose sum is σ = 44698464645120. Its totient is φ = 6951089416320.

The previous prime is 21001111122067. The next prime is 21001111122149. The reversal of 21001111122110 is 1122111110012.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13400555 + ... + 14885465.

It is an arithmetic number, because the mean of its divisors is an integer number (698413510080).

Almost surely, 2^{21001111122110} is an apocalyptic number.

21001111122110 is an abundant number, since it is smaller than the sum of its proper divisors (23697353523010).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21001111122110 is a wasteful number, since it uses less digits than its factorization.

21001111122110 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1491921.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 21001111122110 its reverse (1122111110012), we get a palindrome (22123222232122).

The spelling of 21001111122110 in words is "twenty-one trillion, one billion, one hundred eleven million, one hundred twenty-two thousand, one hundred ten".