# Java program for Prime Number | Check whether Number is Prime or Not

Check Prime Number Example in Java - This program will read an integer number and check whether given number is Prime or Not, in this program we will divide number from 2 to number/2, if number divide by any number then number will not be prime number.

## Check Prime Number using Java Program

```//Java program for Prime Number

import java.util.*;

public class Prime
{
public static void main(String args[]){
int num,loop;
boolean flag=false;

Scanner bf=new Scanner(System.in);

//input an integer number
System.out.print("Enter any integer number: ");
num= bf.nextInt();

//check prime
for(loop=2; loop<=(num/2); loop++)
{
if(num%loop==0)
{
flag=true;
break;
}
}

if(flag==false)
System.out.println(num + " is a prime number.");
else
System.out.println(num + " is not a prime number.");
}
}
```

Output

```
[email protected]:~\$ javac Prime.java
[email protected]:~\$ java Prime
Enter any integer number: 79
79 is a prime number.

```

#### Using function/Method

```//Java program for Prime Number

import java.util.*;

public class Prime
{
//function to check number is prime or not
public static boolean isPrime(int num)
{
//check prime
for(int loop=2; loop<=(num/2); loop++)
{
if(num%loop==0)
return false;
}

return true;
}

public static void main(String args[]){
int num,loop;
boolean flag=false;

Scanner bf=new Scanner(System.in);

//input an integer number
System.out.print("Enter any integer number: ");
num= bf.nextInt();

if(isPrime(num))
System.out.println(num + " is a prime number.");
else
System.out.println(num + " is not a prime number.");
}
}
```

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