#iterative approach
def findMinSum(num):
   sum_ = 0
   # Find factors of number and add to the sum
   i = 2
   while(i * i <= num):
      while(num % i == 0):
         sum_ += i
         num /= i
      i += 1
   sum_ += num
   return sum_
# Driver Code
num = 12
print (findMinSum(num))