320644 has 12 divisors (see below), whose sum is σ = 590800. Its totient is φ = 151848.

The previous prime is 320627. The next prime is 320647. The reversal of 320644 is 446023.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is not an unprimeable number, because it can be changed into a prime (320647) by changing a digit.

320644 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2034 + ... + 2185.

2³²⁰⁶⁴⁴ is an apocalyptic number.

It is an amenable number.

320644 is a deficient number, since it is larger than the sum of its proper divisors (270156).

320644 is a wasteful number, since it uses less digits than its factorization.

320644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4242 (or 4240 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 19.

The square root of 320644 is about 566.2543598066. The cubic root of 320644 is about 68.4448914753. Note that the first 3 decimals are identical.

Adding to 320644 its reverse (446023), we get a palindrome (766667).

The spelling of 320644 in words is "three hundred twenty thousand, six hundred forty-four".