202021122181 has 2 divisors, whose sum is σ = 202021122182. Its totient is φ = 202021122180.

The previous prime is 202021122169. The next prime is 202021122239. The reversal of 202021122181 is 181221120202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 135151816900 + 66869305281 = 367630^2 + 258591^2 .

It is a cyclic number.

It is not a de Polignac number, because 202021122181 - 2⁹ = 202021121669 is a prime.

It is a super-2 number, since 2×202021122181² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (202021122101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101010561090 + 101010561091.

It is an arithmetic number, because the mean of its divisors is an integer number (101010561091).

Almost surely, 2^202021122181 is an apocalyptic number.

It is an amenable number.

202021122181 is a deficient number, since it is larger than the sum of its proper divisors (1).

202021122181 is an equidigital number, since it uses as much as digits as its factorization.

202021122181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 256, while the sum is 22.

Adding to 202021122181 its reverse (181221120202), we get a palindrome (383242242383).

The spelling of 202021122181 in words is "two hundred two billion, twenty-one million, one hundred twenty-two thousand, one hundred eighty-one".