201221020202161 has 2 divisors, whose sum is σ = 201221020202162. Its totient is φ = 201221020202160.

The previous prime is 201221020202149. The next prime is 201221020202243. The reversal of 201221020202161 is 161202020122102.

201221020202161 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 160391079993600 + 40829940208561 = 12664560^2 + 6389831^2 .

It is a cyclic number.

It is not a de Polignac number, because 201221020202161 - 2²⁹ = 201220483331249 is a prime.

It is not a weakly prime, because it can be changed into another prime (201221020202861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100610510101080 + 100610510101081.

It is an arithmetic number, because the mean of its divisors is an integer number (100610510101081).

Almost surely, 2^{201221020202161} is an apocalyptic number.

It is an amenable number.

201221020202161 is a deficient number, since it is larger than the sum of its proper divisors (1).

201221020202161 is an equidigital number, since it uses as much as digits as its factorization.

201221020202161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 384, while the sum is 22.

Adding to 201221020202161 its reverse (161202020122102), we get a palindrome (362423040324263).

The spelling of 201221020202161 in words is "two hundred one trillion, two hundred twenty-one billion, twenty million, two hundred two thousand, one hundred sixty-one".