main(i){
int n;
scanf("%d",&n);
for(i='';i<n&&~i&' ';){
	if(!(n%i)){
		puts("NO");
		return !i;
	}
	if(~i&'
')i^='
';
	else if(~i&'')i^='';
	else if(~i&'')i^='';
	else if(~i&'')i^='';
	else if(~i&'')i^='';
	else if(~i&' ')i^='?';
}
puts(n=='
'?"NO":"YES");
}