806509 has 8 divisors (see below), whose sum is σ = 887328. Its totient is φ = 726960.

The previous prime is 806503. The next prime is 806513. The reversal of 806509 is 905608.

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 806509 - 2⁷ = 806381 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 (806503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1494 + ... + 1960.

It is an arithmetic number, because the mean of its divisors is an integer number (110916).

2⁸⁰⁶⁵⁰⁹ is an apocalyptic number.

It is an amenable number.

806509 is a deficient number, since it is larger than the sum of its proper divisors (80819).

806509 is a wasteful number, since it uses less digits than its factorization.

806509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 635.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 806509 is about 898.0584613487. The cubic root of 806509 is about 93.0828644419.

Subtracting 806509 from its reverse (905608), we obtain a palindrome (99099).

The spelling of 806509 in words is "eight hundred six thousand, five hundred nine".