21210111211110 has 64 divisors (see below), whose sum is σ = 53587008933120. Its totient is φ = 5357986876800.

The previous prime is 21210111211097. The next prime is 21210111211111. The reversal of 21210111211110 is 1111211101212.

It is a super-2 number, since 2×21210111211110² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21210111211110.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21210111211111) by changing a digit.

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, 7375509 + ... + 9839631.

It is an arithmetic number, because the mean of its divisors is an integer number (837297014580).

Almost surely, 2^{21210111211110} is an apocalyptic number.

21210111211110 is an abundant number, since it is smaller than the sum of its proper divisors (32376897722010).

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

21210111211110 is a wasteful number, since it uses less digits than its factorization.

21210111211110 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2479253.

The product of its (nonzero) digits is 8, while the sum is 15.

Adding to 21210111211110 its reverse (1111211101212), we get a palindrome (22321322312322).

The spelling of 21210111211110 in words is "twenty-one trillion, two hundred ten billion, one hundred eleven million, two hundred eleven thousand, one hundred ten".