163565 has 4 divisors (see below), whose sum is σ = 196284. Its totient is φ = 130848.

The previous prime is 163561. The next prime is 163567. The reversal of 163565 is 565361.

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

It can be written as a sum of positive squares in 2 ways, for example, as 72361 + 91204 = 269^2 + 302^2 .

It is a cyclic number.

It is not a de Polignac number, because 163565 - 2² = 163561 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 (163561) by changing a digit.

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, 16352 + ... + 16361.

It is an arithmetic number, because the mean of its divisors is an integer number (49071).

2¹⁶³⁵⁶⁵ is an apocalyptic number.

It is an amenable number.

163565 is a deficient number, since it is larger than the sum of its proper divisors (32719).

163565 is an equidigital number, since it uses as much as digits as its factorization.

163565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32718.

The product of its digits is 2700, while the sum is 26.

The square root of 163565 is about 404.4317000434. The cubic root of 163565 is about 54.6885983453.

It can be divided in two parts, 16356 and 5, that added together give a palindrome (16361).

The spelling of 163565 in words is "one hundred sixty-three thousand, five hundred sixty-five".