In this tutorial, we will write a program to check whether the number is prime or not in java. Before that, you should have knowledge on the following topic in java.
A number is said to be a prime number if it is divisible by itself and 1. Example: 3, 5, 7, 11, 13, 17, 19, etc.
We take a boolean variable isPrime and assigned it to be true. Then we take the user input and start a for loop for i = 2 end the loop for i less than half of the number entered. i will increase by 1 after each iteration.
Inside for loop, a temp variable will contain the remainder of each iteration. And then if statement will check for temp to be 0 that is if the remainder is zero, isPrime is set to false. If isPrime is true, the number is Prime number else not.
Java Program to check whether a Number is Prime or Not
source code: Java Program to check for the prime number.
//check for the prime Number
public class PrimrNumberCheck
public static void main(String args)
boolean isPrime = true;
Scanner scan = new Scanner(System.in);
System.out.print("Enter any number: ");
int num = scan.nextInt();
for (int i = 2; i <= num / 2; i++)
temp = num % i;
if (temp == 0)
isPrime = false;
System.out.println(num + " is a Prime Number"); //If isPrime is true
System.out.println(num + " is not a Prime Number"); //If isPrime is false
Enter any number: 13
13 is a Prime Number