21002220210221 has 8 divisors (see below), whose sum is σ = 21006629049600. Its totient is φ = 20997811628640.

The previous prime is 21002220210173. The next prime is 21002220210247. The reversal of 21002220210221 is 12201202220012.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21002220210221 - 2⁶ = 21002220210157 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21002220210221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002220210821) 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, 296275460 + ... + 296346338.

It is an arithmetic number, because the mean of its divisors is an integer number (2625828631200).

Almost surely, 2^{21002220210221} is an apocalyptic number.

It is an amenable number.

21002220210221 is a deficient number, since it is larger than the sum of its proper divisors (4408839379).

21002220210221 is an equidigital number, since it uses as much as digits as its factorization.

21002220210221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128899.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21002220210221 its reverse (12201202220012), we get a palindrome (33203422430233).

The spelling of 21002220210221 in words is "twenty-one trillion, two billion, two hundred twenty million, two hundred ten thousand, two hundred twenty-one".