202221202121 has 2 divisors, whose sum is σ = 202221202122. Its totient is φ = 202221202120.

The previous prime is 202221202111. The next prime is 202221202123. The reversal of 202221202121 is 121202122202.

It is a happy number.

202221202121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 197451366025 + 4769836096 = 444355^2 + 69064^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-202221202121 is a prime.

Together with 202221202123, 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 202221202121.

It is not a weakly prime, because it can be changed into another prime (202221202123) by changing a digit.

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 as a sum of consecutive naturals, namely, 101110601060 + 101110601061.

It is an arithmetic number, because the mean of its divisors is an integer number (101110601061).

Almost surely, 2^202221202121 is an apocalyptic number.

It is an amenable number.

202221202121 is a deficient number, since it is larger than the sum of its proper divisors (1).

202221202121 is an equidigital number, since it uses as much as digits as its factorization.

202221202121 is an odious number, because the sum of its binary digits is odd.

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

Adding to 202221202121 its reverse (121202122202), we get a palindrome (323423324323).

The spelling of 202221202121 in words is "two hundred two billion, two hundred twenty-one million, two hundred two thousand, one hundred twenty-one".