523813 has 4 divisors (see below), whose sum is σ = 530208. Its totient is φ = 517420.

The previous prime is 523801. The next prime is 523829. The reversal of 523813 is 318325.

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 a cyclic number.

It is not a de Polignac number, because 523813 - 2¹³ = 515621 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

523813 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (523213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3073 + ... + 3238.

It is an arithmetic number, because the mean of its divisors is an integer number (132552).

2⁵²³⁸¹³ is an apocalyptic number.

It is an amenable number.

523813 is a deficient number, since it is larger than the sum of its proper divisors (6395).

523813 is an equidigital number, since it uses as much as digits as its factorization.

523813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6394.

The product of its digits is 720, while the sum is 22.

The square root of 523813 is about 723.7492659754. The cubic root of 523813 is about 80.6105883341.

The spelling of 523813 in words is "five hundred twenty-three thousand, eight hundred thirteen".