n=int(input())
p=[*range(n+1)]
p[1]=1
for i in range(2,n+1):
  if p[i]<i:continue
  for j in range(i*i,n+1,i):p[j]=i

ans=0
for i in range(2,n+1):
  q=[]
  for j in range(4):
    q.append(p[i])
    i//=p[i]
  if i==1 and len(set(q))==4 and 1 not in q:
    ans+=1

print(ans)