813309 has 8 divisors (see below), whose sum is σ = 1239360. Its totient is φ = 464736.

The previous prime is 813301. The next prime is 813311. The reversal of 813309 is 903318.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 813309 - 2³ = 813301 is a prime.

It is a super-2 number, since 2×813309² = 1322943058962, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (813301) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19344 + ... + 19385.

It is an arithmetic number, because the mean of its divisors is an integer number (154920).

2⁸¹³³⁰⁹ is an apocalyptic number.

It is an amenable number.

813309 is a deficient number, since it is larger than the sum of its proper divisors (426051).

813309 is a wasteful number, since it uses less digits than its factorization.

813309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38739.

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 813309 is about 901.8364596755. The cubic root of 813309 is about 93.3437389192.

Subtracting 813309 from its reverse (903318), we obtain a palindrome (90009).

The spelling of 813309 in words is "eight hundred thirteen thousand, three hundred nine".