166505659 has 4 divisors (see below), whose sum is σ = 166532904. Its totient is φ = 166478416.

The previous prime is 166505639. The next prime is 166505663. The reversal of 166505659 is 956505661.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166505659 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166505609) 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 in 3 ways as a sum of consecutive naturals, for example, 264 + ... + 18250.

It is an arithmetic number, because the mean of its divisors is an integer number (41633226).

Almost surely, 2^166505659 is an apocalyptic number.

166505659 is a deficient number, since it is larger than the sum of its proper divisors (27245).

166505659 is an equidigital number, since it uses as much as digits as its factorization.

166505659 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27244.

The product of its (nonzero) digits is 243000, while the sum is 43.

The square root of 166505659 is about 12903.7071804966. The cubic root of 166505659 is about 550.1439391862.

The spelling of 166505659 in words is "one hundred sixty-six million, five hundred five thousand, six hundred fifty-nine".