321328 has 40 divisors (see below), whose sum is σ = 753920. Its totient is φ = 129600.

The previous prime is 321323. The next prime is 321329. The reversal of 321328 is 823123.

It is a happy number.

321328 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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 (321323) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2053 + ... + 2203.

It is an arithmetic number, because the mean of its divisors is an integer number (18848).

2³²¹³²⁸ is an apocalyptic number.

321328 is a gapful number since it is divisible by the number (38) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 321328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (376960).

321328 is an abundant number, since it is smaller than the sum of its proper divisors (432592).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

321328 is a wasteful number, since it uses less digits than its factorization.

321328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185 (or 179 counting only the distinct ones).

The product of its digits is 288, while the sum is 19.

The square root of 321328 is about 566.8580069118. The cubic root of 321328 is about 68.4935259479.

The spelling of 321328 in words is "three hundred twenty-one thousand, three hundred twenty-eight".