N=int(input()) import math I=int(True) num=[I,I] z=math.log(I,len(num)) print(z) need=int(math.sqrt(N)) for a in range(need): if N%len(num)==0: ans="NO" break else: ans="YES" num.append(I) if N==I: ans="NO" elif N==round(math.log(len(num),math.sqrt(len(num)))): ans="YES" print(ans)