166123189 has 2 divisors, whose sum is σ = 166123190. Its totient is φ = 166123188.

The previous prime is 166123169. The next prime is 166123193. The reversal of 166123189 is 981321661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 93276964 + 72846225 = 9658^2 + 8535^2 .

It is a cyclic number.

It is not a de Polignac number, because 166123189 - 2⁵ = 166123157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166123109) 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, 83061594 + 83061595.

It is an arithmetic number, because the mean of its divisors is an integer number (83061595).

Almost surely, 2^166123189 is an apocalyptic number.

It is an amenable number.

166123189 is a deficient number, since it is larger than the sum of its proper divisors (1).

166123189 is an equidigital number, since it uses as much as digits as its factorization.

166123189 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 37.

The square root of 166123189 is about 12888.8785004747. The cubic root of 166123189 is about 549.7223822074.

The spelling of 166123189 in words is "one hundred sixty-six million, one hundred twenty-three thousand, one hundred eighty-nine".