805813 has 4 divisors (see below), whose sum is σ = 808108. Its totient is φ = 803520.

The previous prime is 805811. The next prime is 805843. The reversal of 805813 is 318508.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 27889 + 777924 = 167^2 + 882^2 .

It is a cyclic number.

It is not a de Polignac number, because 805813 - 2¹ = 805811 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 (805811) 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, 498 + ... + 1363.

It is an arithmetic number, because the mean of its divisors is an integer number (202027).

2⁸⁰⁵⁸¹³ is an apocalyptic number.

It is an amenable number.

805813 is a deficient number, since it is larger than the sum of its proper divisors (2295).

805813 is a wasteful number, since it uses less digits than its factorization.

805813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2294.

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 805813 is about 897.6708750984. The cubic root of 805813 is about 93.0560805627.

The spelling of 805813 in words is "eight hundred five thousand, eight hundred thirteen".