def check_num(n):
  ok1=True
  ok2=False
  for i in range(1,int(n**0.5)+1):
    if n%i==0:
      if 2<=i<=100000:
        ok1=False
        break
  for i in range(2,int(n**0.5)+1):
    if n%i==0:
      ok2=True
      break
  return True if ok1==True and ok2==True else False

N=int(input())
a=[1]
for i in range(10**5,10**5+10001):
  if check_num(i):a.append(i)
print(a[N-1])