21201100111220 has 24 divisors (see below), whose sum is σ = 45149385028608. Its totient is φ = 8360997226400.

The previous prime is 21201100111181. The next prime is 21201100111249. The reversal of 21201100111220 is 2211100110212.

It is a junction number, because it is equal to n+sod(n) for n = 21201100111195 and 21201100111204.

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 7 ways as a sum of consecutive naturals, for example, 7465174676 + ... + 7465177515.

It is an arithmetic number, because the mean of its divisors is an integer number (1881224376192).

Almost surely, 2^{21201100111220} is an apocalyptic number.

21201100111220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21201100111220 is an abundant number, since it is smaller than the sum of its proper divisors (23948284917388).

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

21201100111220 is a wasteful number, since it uses less digits than its factorization.

21201100111220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14930352271 (or 14930352269 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21201100111220 its reverse (2211100110212), we get a palindrome (23412200221432).

The spelling of 21201100111220 in words is "twenty-one trillion, two hundred one billion, one hundred million, one hundred eleven thousand, two hundred twenty".