<?php
$n = trim(fgets(STDIN));
$fact_time = 0;
for ( $i=2; ($i*$i)<=$n; $i++ ) {
	while ( !($n % $i) ) {
		$n /= $i;
		$fact_time++;
		if ( $fact_time > 2 ) {
			break 2;
		}
	}
}
if ( $n > 1 ) {
	$fact_time++;
}
if ( $fact_time > 2 ) {
	echo "YES".PHP_EOL;
}
else {
	echo "NO".PHP_EOL;
}