166811189 has 2 divisors, whose sum is σ = 166811190. Its totient is φ = 166811188.

The previous prime is 166811167. The next prime is 166811221. The reversal of 166811189 is 981118661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 149255089 + 17556100 = 12217^2 + 4190^2 .

It is a cyclic number.

It is not a de Polignac number, because 166811189 - 2⁸ = 166810933 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166811119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83405594 + 83405595.

It is an arithmetic number, because the mean of its divisors is an integer number (83405595).

Almost surely, 2^166811189 is an apocalyptic number.

It is an amenable number.

166811189 is a deficient number, since it is larger than the sum of its proper divisors (1).

166811189 is an equidigital number, since it uses as much as digits as its factorization.

166811189 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20736, while the sum is 41.

The square root of 166811189 is about 12915.5406003775. The cubic root of 166811189 is about 550.4802296038.

The spelling of 166811189 in words is "one hundred sixty-six million, eight hundred eleven thousand, one hundred eighty-nine".