use proconio::input;

fn main(){
    input!{
        n: u64,
    }

    let mut ok = true;
    let mut p = 2;
    while p*p <= n{
        if n%p == 0{
            ok = false;
        }
        p += 1;
    }

    println!("{}", if !ok{"YES"} else{"NO"});
}