while(number>0) //Until the number is zero keep running the loop
        {
        rev_number*=10; //Multiply by 10 and keep adding remainders until you reach zero
        rev_number+=number%10; //Add the remainder to the rev_number variable
        number/=10; //Divide the number to be reversed by 10
        }

Make sure you change the variable names but not the order of the operation. Otherwise you'll fuck shit up