#yuki1737
def prime_factorize(n):
 a = []
 while n%2==0:
  a.append(2)
  n//=2
 f = 3
 while f*f<=n:
  if n%f==0:
   a.append(f)
   n//=f
  else:
   f+=2
 if n!=1:
  a.append(n)
 return a
    
n=int(input())
l=prime_factorize(n)
print(sum(l))