SMITH MUMBER

A smith number is a composite number, the sum of whose digits is the sum of the digits of its prime factors obtained as a result of prime factorization (excluding 1).
The first few such numbers are 4, 22, 27, 58, 85, 94, 121
Example
1. 666
Prime factors are 2, 3, 3 and 37
Sum of the digits are (6+6+6) = 18
Sum of the digits of the factors (2+3+3+(3+7) = 18
2. 4937775
Prime factors are 3, 5, 5, 65837
Sum of the digits are (4+9+3+7+7+7+5) = 42
Sum of the digits (factors) (3+5+5+(6+5+8+3+7)=42
Write a program to input a number and display whether the number is a Smith number or not

import java.util.Scanner; 
public class Smith
{
    int n;
    public Smith() 
    {
    }
    public void input()
    {
        Scanner sc = new Scanner(System.in);
        System.out.println("\nEnter a positive natural number  ");
        n=sc.nextInt();     
    } 
int sumDig(int in)
    {
        int s=0;
        while(in>0)
        {
            s=s+in%10;
            in=in/10;
        }
        return s;
    }
int sumPrimeFact()
    {
        int i=2, sum=0;
        while(n>1)
        {
            if(n%i==0)
            {
                sum=sum+sumDig(i); 
                  //Here 'i' is the prime factor of 'n' 
                n=n/i;
            }
            else
                i++;
        }
        return sum;
    }
public  void isSmith() 
 {
   int a=sumDig(n);// finding sum of digit
   int b=sumPrimeFact(); //finding sum of primefactors 
   System.out.println("Sum of Digit = "+a);
   System.out.println("Sum of Prime Factor = "+b);   
   if(a==b)
      System.out.print("It is a Smith Number");
   else 
      System.out.print("It is Not a Smith Number");
  } 
public static void main()
    {
        Smith obj = new Smith();
        obj.input();
        obj.isSmith();
    }