210121201122169 has 2 divisors, whose sum is σ = 210121201122170. Its totient is φ = 210121201122168.

The previous prime is 210121201122167. The next prime is 210121201122179. The reversal of 210121201122169 is 961221102121012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 209029050718569 + 1092150403600 = 14457837^2 + 1045060^2 .

It is a cyclic number.

It is not a de Polignac number, because 210121201122169 - 2¹ = 210121201122167 is a prime.

It is a super-2 number, since 2×210121201122169² (a number of 29 digits) contains 22 as substring.

Together with 210121201122167, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 210121201122169.

It is not a weakly prime, because it can be changed into another prime (210121201122167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105060600561084 + 105060600561085.

It is an arithmetic number, because the mean of its divisors is an integer number (105060600561085).

Almost surely, 2^{210121201122169} is an apocalyptic number.

It is an amenable number.

210121201122169 is a deficient number, since it is larger than the sum of its proper divisors (1).

210121201122169 is an equidigital number, since it uses as much as digits as its factorization.

210121201122169 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 31.

The spelling of 210121201122169 in words is "two hundred ten trillion, one hundred twenty-one billion, two hundred one million, one hundred twenty-two thousand, one hundred sixty-nine".