2021001222221 has 2 divisors, whose sum is σ = 2021001222222. Its totient is φ = 2021001222220.

The previous prime is 2021001222181. The next prime is 2021001222223. The reversal of 2021001222221 is 1222221001202.

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., 1371065355625 + 649935866596 = 1170925^2 + 806186^2 .

It is a cyclic number.

It is not a de Polignac number, because 2021001222221 - 2⁶ = 2021001222157 is a prime.

Together with 2021001222223, 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 2021001222221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2021001222223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1010500611110 + 1010500611111.

It is an arithmetic number, because the mean of its divisors is an integer number (1010500611111).

Almost surely, 2^{2021001222221} is an apocalyptic number.

It is an amenable number.

2021001222221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2021001222221 is an equidigital number, since it uses as much as digits as its factorization.

2021001222221 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 2021001222221 its reverse (1222221001202), we get a palindrome (3243222223423).

The spelling of 2021001222221 in words is "two trillion, twenty-one billion, one million, two hundred twenty-two thousand, two hundred twenty-one".