166565 has 8 divisors (see below), whose sum is σ = 228480. Its totient is φ = 114192.

The previous prime is 166561. The next prime is 166567. The reversal of 166565 is 565661.

166565 is an esthetic number in base 15, because in such base its adjacent digits differ by 1.

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 166565 - 2² = 166561 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166561) 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, 2345 + ... + 2414.

It is an arithmetic number, because the mean of its divisors is an integer number (28560).

2¹⁶⁶⁵⁶⁵ is an apocalyptic number.

It is an amenable number.

166565 is a deficient number, since it is larger than the sum of its proper divisors (61915).

166565 is an equidigital number, since it uses as much as digits as its factorization.

166565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4771.

The product of its digits is 5400, while the sum is 29.

The square root of 166565 is about 408.1237557408. The cubic root of 166565 is about 55.0209286743.

It can be divided in two parts, 16656 and 5, that added together give a palindrome (16661).

The spelling of 166565 in words is "one hundred sixty-six thousand, five hundred sixty-five".