209065 has 4 divisors (see below), whose sum is σ = 250884. Its totient is φ = 167248.

The previous prime is 209063. The next prime is 209071. The reversal of 209065 is 560902.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 560902 = 2 ⋅280451.

It can be written as a sum of positive squares in 2 ways, for example, as 46656 + 162409 = 216^2 + 403^2 .

It is a cyclic number.

It is not a de Polignac number, because 209065 - 2¹ = 209063 is a prime.

It is a super-3 number, since 3×209065³ = 27413548333048875, which contains 333 as substring.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

209065 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209063) 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, 20902 + ... + 20911.

It is an arithmetic number, because the mean of its divisors is an integer number (62721).

2²⁰⁹⁰⁶⁵ is an apocalyptic number.

It is an amenable number.

209065 is a deficient number, since it is larger than the sum of its proper divisors (41819).

209065 is an equidigital number, since it uses as much as digits as its factorization.

209065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41818.

The product of its (nonzero) digits is 540, while the sum is 22.

The square root of 209065 is about 457.2362627789. The cubic root of 209065 is about 59.3508729304.

Adding to 209065 its reverse (560902), we get a palindrome (769967).

The spelling of 209065 in words is "two hundred nine thousand, sixty-five".