21220001202221 has 8 divisors (see below), whose sum is σ = 21475870790304. Its totient is φ = 20964136541040.

The previous prime is 21220001202217. The next prime is 21220001202271. The reversal of 21220001202221 is 12220210002212.

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 21220001202221 - 2² = 21220001202217 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 21220001202221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220001202271) 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, 7833995 + ... + 10188791.

It is an arithmetic number, because the mean of its divisors is an integer number (2684483848788).

Almost surely, 2^{21220001202221} is an apocalyptic number.

It is an amenable number.

21220001202221 is a deficient number, since it is larger than the sum of its proper divisors (255869588083).

21220001202221 is a wasteful number, since it uses less digits than its factorization.

21220001202221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2463451.

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

Adding to 21220001202221 its reverse (12220210002212), we get a palindrome (33440211204433).

The spelling of 21220001202221 in words is "twenty-one trillion, two hundred twenty billion, one million, two hundred two thousand, two hundred twenty-one".