210221202221 has 2 divisors, whose sum is σ = 210221202222. Its totient is φ = 210221202220.

The previous prime is 210221202209. The next prime is 210221202223. The reversal of 210221202221 is 122202122012.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 192958132900 + 17263069321 = 439270^2 + 131389^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-210221202221 is a prime.

Together with 210221202223, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 210221202221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (210221202223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105110601110 + 105110601111.

It is an arithmetic number, because the mean of its divisors is an integer number (105110601111).

Almost surely, 2^210221202221 is an apocalyptic number.

It is an amenable number.

210221202221 is a deficient number, since it is larger than the sum of its proper divisors (1).

210221202221 is an equidigital number, since it uses as much as digits as its factorization.

210221202221 is an evil number, because the sum of its binary digits is even.

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

Adding to 210221202221 its reverse (122202122012), we get a palindrome (332423324233).

The spelling of 210221202221 in words is "two hundred ten billion, two hundred twenty-one million, two hundred two thousand, two hundred twenty-one".