813505 has 16 divisors (see below), whose sum is σ = 1217664. Its totient is φ = 506880.

The previous prime is 813503. The next prime is 813511. The reversal of 813505 is 505318.

It is not a de Polignac number, because 813505 - 2¹ = 813503 is a prime.

813505 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (813503) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 672 + ... + 1441.

It is an arithmetic number, because the mean of its divisors is an integer number (76104).

2⁸¹³⁵⁰⁵ is an apocalyptic number.

It is an amenable number.

813505 is a deficient number, since it is larger than the sum of its proper divisors (404159).

813505 is a wasteful number, since it uses less digits than its factorization.

813505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2136.

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 813505 is about 901.9451202817. The cubic root of 813505 is about 93.3512366449.

The spelling of 813505 in words is "eight hundred thirteen thousand, five hundred five".