166611161 has 2 divisors, whose sum is σ = 166611162. Its totient is φ = 166611160.

The previous prime is 166611139. The next prime is 166611163. The reversal of 166611161 is 161116661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 165611161 + 1000000 = 12869^2 + 1000^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166611161 is a prime.

Together with 166611163, 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 (166611163) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83305580 + 83305581.

It is an arithmetic number, because the mean of its divisors is an integer number (83305581).

Almost surely, 2^166611161 is an apocalyptic number.

It is an amenable number.

166611161 is a deficient number, since it is larger than the sum of its proper divisors (1).

166611161 is an equidigital number, since it uses as much as digits as its factorization.

166611161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1296, while the sum is 29.

The square root of 166611161 is about 12907.7945831191. The cubic root of 166611161 is about 550.2601094749.

The spelling of 166611161 in words is "one hundred sixty-six million, six hundred eleven thousand, one hundred sixty-one".