### Java Program to Check Prime Number - The Coding Shala

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In this post, we will learn how to Check if a Given Number is a Prime Number or not in Java.

## Java Program to Check Prime Number

A Prime Number is a number that is divisible by 1 and the number itself. For example, the number 5 is a Prime Number because it is divisible by 1 and 5 only.

Note: Number 0 and 1 are not prime numbers.

Example 1:
Input: 7
Output: Prime Number

Example 2:
Input: 9
Output: Not a Prime Number

Java Program:

```// Java program to Check Prime Number

import java.util.Scanner;

public class Main {

static boolean isPrime(int num) {
if(num < 2) return false;

//  basic for loop ==> for(int i = 2; i < num / 2; i++ )
for(int i = 2; i * i <= num; i++) {
if(num % i == 0) return false;
}
return true;
}

public static void main(String[] args) {
Scanner sc = new Scanner(System.in);

// take input char
System.out.println("Enter the Number: ");
int num = sc.nextInt();

if(isPrime(num)) {
System.out.println(num + " is a Prime Number");
} else {
System.out.println(num + " is not a Prime Number");
}

sc.close();
}
}
```

Output:

```Enter the Number:
8
8 is not a Prime Number
```

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