166385693 has 4 divisors (see below), whose sum is σ = 166580700. Its totient is φ = 166190688.

The previous prime is 166385671. The next prime is 166385741. The reversal of 166385693 is 396583661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 396583661 = 1481 ⋅267781.

It can be written as a sum of positive squares in 2 ways, for example, as 64032004 + 102353689 = 8002^2 + 10117^2 .

It is a cyclic number.

It is not a de Polignac number, because 166385693 - 2⁸ = 166385437 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166385623) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 96218 + ... + 97931.

It is an arithmetic number, because the mean of its divisors is an integer number (41645175).

Almost surely, 2^166385693 is an apocalyptic number.

It is an amenable number.

166385693 is a deficient number, since it is larger than the sum of its proper divisors (195007).

166385693 is an equidigital number, since it uses as much as digits as its factorization.

166385693 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195006.

The product of its digits is 699840, while the sum is 47.

The square root of 166385693 is about 12899.0578338110. The cubic root of 166385693 is about 550.0117826677.

The spelling of 166385693 in words is "one hundred sixty-six million, three hundred eighty-five thousand, six hundred ninety-three".