N=int(input())
f=False
P=[]
if N!=1 and N!=2:
  c=2
  for j in range(2,int(N**0.5)):
    p=False
    k=0
    u=j**0.5
    for v in P:
      if v>u: break
      if j%v==0:
        p=True
        break
    if not p:
      if N%j==0:
        c-=1
        if N%(j**2)==0: c-=1
      if c==0:
        f=True
        break
      P.append(j)
print("YES" if f else "NO")