21200111220221 has 8 divisors (see below), whose sum is σ = 21884038706688. Its totient is φ = 20516187042000.

The previous prime is 21200111220203. The next prime is 21200111220257. The reversal of 21200111220221 is 12202211100212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21200111220221 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21200111220221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21200141220221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24865016 + ... + 25703486.

It is an arithmetic number, because the mean of its divisors is an integer number (2735504838336).

Almost surely, 2^{21200111220221} is an apocalyptic number.

It is an amenable number.

21200111220221 is a deficient number, since it is larger than the sum of its proper divisors (683927486467).

21200111220221 is an equidigital number, since it uses as much as digits as its factorization.

21200111220221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1654123.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21200111220221 its reverse (12202211100212), we get a palindrome (33402322320433).

The spelling of 21200111220221 in words is "twenty-one trillion, two hundred billion, one hundred eleven million, two hundred twenty thousand, two hundred twenty-one".