Java BigInt Factorial

Simple program written in Java to calculate Big Integer factorial.

import java.lang.String;
import java.math.BigInteger;
import java.util.Scanner;

// ? 2017 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(factorial(n));
  }
  
  static BigInteger factorial(int N){
    BigInteger f = new BigInteger("1"); 
 
    for (int i = 2; i <= N; i++){
       f = f.multiply(BigInteger.valueOf(i));
    }     
 
    return f;
  }
}