320813 has 4 divisors (see below), whose sum is σ = 321948. Its totient is φ = 319680.

The previous prime is 320791. The next prime is 320821. The reversal of 320813 is 318023.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 162409 + 158404 = 403^2 + 398^2 .

It is a cyclic number.

It is not a de Polignac number, because 320813 - 2¹² = 316717 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 320791 and 320800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (320833) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 245 + ... + 837.

It is an arithmetic number, because the mean of its divisors is an integer number (80487).

2³²⁰⁸¹³ is an apocalyptic number.

It is an amenable number.

320813 is a deficient number, since it is larger than the sum of its proper divisors (1135).

320813 is an equidigital number, since it uses as much as digits as its factorization.

320813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1134.

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 320813 is about 566.4035663730. The cubic root of 320813 is about 68.4569143158.

Adding to 320813 its reverse (318023), we get a palindrome (638836).

The spelling of 320813 in words is "three hundred twenty thousand, eight hundred thirteen".