Java Int Primorial

Simple Java program to calculate primorial of given non-negative integer.

import java.util.Scanner;

// 2018 TheFlyingKeyboard and released under MIT License
// theflyingkeyboard.net
public class Main {
    public static void main(String[] args) {
        Scanner reader = new Scanner(System.in);
        int n;

        System.out.println("Enter a number: ");
        n = reader.nextInt(); //Reads integer from keyboard

        System.out.println("Primorial of: " + n + " is equal to: " + primorial(n));
    }

    private static int primorial(int n){
        int prim = 1;
        int counter = 0;
        int i = 1;

        while (counter <= n){
            if(isPrime(i)){
                prim *= i;
                ++counter;
            }

            ++i;
        }

        return prim;
    }

    private static boolean isPrime(int n){
        if(n == 2 || n == 3 || n == 5){
            return false;
        }

        if(n % 2 == 0){
            return false;
        }

        for(int i = 3; i < Math.sqrt(n) + 1; ++i){
            if(n % i == 0){
                return false;
            }
        }

        return true;
    }
}