8009 has 2 divisors, whose sum is σ = 8010. Its totient is φ = 8008.

The previous prime is 7993. The next prime is 8011. The reversal of 8009 is 9008.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7225 + 784 = 85^2 + 28^2 .

It is a cyclic number.

It is not a de Polignac number, because 8009 - 2⁴ = 7993 is a prime.

Together with 8011, it forms a pair of twin primes.

It is a Chen prime.

It is a magnanimous number.

8009 is a modest number, since divided by 9 gives 8 as remainder.

It is a plaindrome in base 15.

It is not a weakly prime, because it can be changed into another prime (8039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4004 + 4005.

It is an arithmetic number, because the mean of its divisors is an integer number (4005).

2⁸⁰⁰⁹ is an apocalyptic number.

It is an amenable number.

8009 is a deficient number, since it is larger than the sum of its proper divisors (1).

8009 is an equidigital number, since it uses as much as digits as its factorization.

8009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 8009 is about 89.4930164873. The cubic root of 8009 is about 20.0074971893.

Subtracting 8009 from its reverse (9008), we obtain a palindrome (999).

The spelling of 8009 in words is "eight thousand, nine".