166745165 has 4 divisors (see below), whose sum is σ = 200094204. Its totient is φ = 133396128.

The previous prime is 166745153. The next prime is 166745171. The reversal of 166745165 is 561547661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 561547661 = 1627 ⋅345143.

It can be written as a sum of positive squares in 2 ways, for example, as 26512201 + 140232964 = 5149^2 + 11842^2 .

It is a cyclic number.

It is not a de Polignac number, because 166745165 - 2¹⁰ = 166744141 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16674512 + ... + 16674521.

It is an arithmetic number, because the mean of its divisors is an integer number (50023551).

Almost surely, 2^166745165 is an apocalyptic number.

It is an amenable number.

166745165 is a deficient number, since it is larger than the sum of its proper divisors (33349039).

166745165 is an equidigital number, since it uses as much as digits as its factorization.

166745165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33349038.

The product of its digits is 151200, while the sum is 41.

The square root of 166745165 is about 12912.9843568402. The cubic root of 166745165 is about 550.4075931836.

The spelling of 166745165 in words is "one hundred sixty-six million, seven hundred forty-five thousand, one hundred sixty-five".