def isprime_Miller(n):
    if n==2: return True
    if n==1 or n&1==0: return False
    
    if n < (1<<32): witness = [2,7,61]
    else: witness = [2, 325, 9375, 28178, 450775, 9780504, 1795265022] # n < (1<<64) でOK 
    #elif n < (1<<61): witness = [2,3,5,7,11,13,17,19,23]
    #if n in witness: return True
    
    d = n-1
    while d&1==0: d >>= 1
    for a in witness:
        t = d
        y = pow(a,t,n)
        while t != n-1 and y != 1 and y != n-1:
            y = y*y%n
            t <<= 1
        if y != n-1 and t&1 == 0: return False
    return True

# coding: utf-8
# Your code here!
import sys
readline = sys.stdin.readline
read = sys.stdin.read

#a,b,c = map(int,readline().split())
n = int(input())
print("NO" if isprime_Miller(n) else "YES")