8209 has 2 divisors, whose sum is σ = 8210. Its totient is φ = 8208.

The previous prime is 8191. The next prime is 8219. The reversal of 8209 is 9028.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5184 + 3025 = 72^2 + 55^2 .

It is a cyclic number.

It is not a de Polignac number, because 8209 - 2⁷ = 8081 is a prime.

It is a d-powerful number, because it can be written as 8 + 0 + 2¹³ + 9 .

It is not a weakly prime, because it can be changed into another prime (8219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (3) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4104 + 4105.

It is an arithmetic number, because the mean of its divisors is an integer number (4105).

2⁸²⁰⁹ is an apocalyptic number.

It is an amenable number.

8209 is a deficient number, since it is larger than the sum of its proper divisors (1).

8209 is an equidigital number, since it uses as much as digits as its factorization.

8209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 8209 is about 90.6035319400. The cubic root of 8209 is about 20.1726716023.

Adding to 8209 its sum of digits (19), we get a palindrome (8228).

The spelling of 8209 in words is "eight thousand, two hundred nine".