166959217 has 2 divisors, whose sum is σ = 166959218. Its totient is φ = 166959216.

The previous prime is 166959197. The next prime is 166959223. The reversal of 166959217 is 712959661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 166823056 + 136161 = 12916^2 + 369^2 .

It is an emirp because it is prime and its reverse (712959661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 166959217 - 2¹¹ = 166957169 is a prime.

It is not a weakly prime, because it can be changed into another prime (166959017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83479608 + 83479609.

It is an arithmetic number, because the mean of its divisors is an integer number (83479609).

Almost surely, 2^166959217 is an apocalyptic number.

It is an amenable number.

166959217 is a deficient number, since it is larger than the sum of its proper divisors (1).

166959217 is an equidigital number, since it uses as much as digits as its factorization.

166959217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 204120, while the sum is 46.

The square root of 166959217 is about 12921.2699453266. The cubic root of 166959217 is about 550.6430132399.

The spelling of 166959217 in words is "one hundred sixty-six million, nine hundred fifty-nine thousand, two hundred seventeen".