# Java Program to Find Factorial of a Number Using Recursion

• Java program to find factorial of a number using recursion.
• Recursive algorithm to find value of factorial of any number.

We have to write a recursive function in Java to calculate factorial of a number. he factorial of a integer N, denoted by N! is the product of all positive integers less than or equal to n.

N! = 1 x 2 x 3 x 4....x (N-2) x (N-1) x N

We can use recursion to calculate factorial of a number because factorial calculation obeys recursive sub-structure property.
Let getfactorial(N) is a function to calculate and return value of N!. To find factorial(N) we can first calculate factorial(N-1) then multiply it with N.

```getfactorial(N) = getfactorial(N-1) x N
N! = (N-1)! x N
N! = 1 x 2 x 3 x 4....x (N-2) x (N-1) x N
```

## Java program to find factorial of a number using recursion

```package com.tcc.java.programs;

import java.util.*;

public class FactorialRecursion {
public static void main(String args[]) {
int num, factorial = 1, i;

Scanner in = new Scanner(System.in);
System.out.println("Enter an Integer");
num = in.nextInt();
factorial = getfactorial(num);

System.out.println("!" + num + " = " + factorial);
}

public static int getfactorial(int num) {
if (num <= 1)
return 1;
return num * getfactorial(num-1);
}
}
```
Output
```Enter an Integer
6
!6 = 720
```