813009 has 4 divisors (see below), whose sum is σ = 1084016. Its totient is φ = 542004.

The previous prime is 812969. The next prime is 813013. The reversal of 813009 is 900318.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 813009 - 2¹¹ = 810961 is a prime.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (813049) 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 3 ways as a sum of consecutive naturals, for example, 135499 + ... + 135504.

It is an arithmetic number, because the mean of its divisors is an integer number (271004).

2⁸¹³⁰⁰⁹ is an apocalyptic number.

It is an amenable number.

813009 is a deficient number, since it is larger than the sum of its proper divisors (271007).

813009 is a wasteful number, since it uses less digits than its factorization.

813009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 271006.

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 813009 is about 901.6701170606. The cubic root of 813009 is about 93.3322604752.

The spelling of 813009 in words is "eight hundred thirteen thousand, nine".