166617161 has 2 divisors, whose sum is σ = 166617162. Its totient is φ = 166617160.

The previous prime is 166617149. The next prime is 166617163. The reversal of 166617161 is 161716661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 157879225 + 8737936 = 12565^2 + 2956^2 .

It is a cyclic number.

It is not a de Polignac number, because 166617161 - 2⁶ = 166617097 is a prime.

It is a super-2 number, since 2×166617161² = 55522556679399842, which contains 22 as substring.

Together with 166617163, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (166617163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83308580 + 83308581.

It is an arithmetic number, because the mean of its divisors is an integer number (83308581).

Almost surely, 2^166617161 is an apocalyptic number.

It is an amenable number.

166617161 is a deficient number, since it is larger than the sum of its proper divisors (1).

166617161 is an equidigital number, since it uses as much as digits as its factorization.

166617161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9072, while the sum is 35.

The square root of 166617161 is about 12908.0269987322. The cubic root of 166617161 is about 550.2667147167.

The spelling of 166617161 in words is "one hundred sixty-six million, six hundred seventeen thousand, one hundred sixty-one".