is_prime = [True]*(10**7)

for i in range(2, 10**7):
  if is_prime[i]:
    j = 2
    while i*j < 10**7:
      is_prime[i*j] = False
      j += 1

primes = []

for i in range(2, 10**7):
  if is_prime[i]:
    primes.append(i)

M = len(primes)
ans = 1

def solve(pre, val, cnt):
  global ans
  for i in range(pre+1, M):
    if val * primes[i] > N:
      break
    ans += (-1)**(cnt+1)
    solve(i, val * primes[i], cnt + 1)

N = int(input())

solve(-1, 1, 0)

print(ans)