C Program to Check whether a Number is Strong or Not

It is a number in which the sum of the factorials of digits of the number is equal to the original number. 

E.g.: n=145=> 1! + 4! + 5! = 1 + 24 + 120 = 145 

so it is strong number.

#include<stdio.h>

#include<conio.h>

int factorial(int);

void main()

{

    int num,temp,rem,strong=0;

    printf("Enter a number:");

    scanf("%d",&num);

    temp=num;

    while(num>0)

    {

        rem=num%10;

        strong=strong+factorial(rem);

        num=num/10;

    }

    if(temp==strong)

        printf("%d is strong number",temp);

    else

        printf("%d is not strong number",temp);

    getch();

}

int factorial(int r)

{

    int i,f=1;

    for(i=r;i>=1;i--)

    {

        f=f*i;

    }

    return f;

}

OUTPUT:

Enter a number:23

23 is not strong number

Enter a number:145

145 is strong number

C Program to Dispaly Strong Numbers between Two Intervals >>