166666985 has 8 divisors (see below), whose sum is σ = 200076480. Its totient is φ = 133282864.

The previous prime is 166666949. The next prime is 166666987. The reversal of 166666985 is 589666661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 166666985 - 2⁶ = 166666921 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (166666987) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14114 + ... + 23076.

It is an arithmetic number, because the mean of its divisors is an integer number (25009560).

Almost surely, 2^166666985 is an apocalyptic number.

It is an amenable number.

166666985 is a deficient number, since it is larger than the sum of its proper divisors (33409495).

166666985 is an equidigital number, since it uses as much as digits as its factorization.

166666985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12687.

The product of its digits is 2799360, while the sum is 53.

The square root of 166666985 is about 12909.9568163492. The cubic root of 166666985 is about 550.3215585201.

The spelling of 166666985 in words is "one hundred sixty-six million, six hundred sixty-six thousand, nine hundred eighty-five".