import std.conv, std.stdio, std.string;

enum long zero     = ``.length;
enum long one      = `u`.length;
enum long two      = `us`.length;
enum long three    = `usa`.length;
enum long four     = `usag`.length;
enum long five     = `usagi`.length;
enum long six      = `usagiu`.length;
enum long seven    = `usagius`.length;
enum long eight    = `usagiusa`.length;
enum long nine     = `usagiusag`.length;
enum long ten      = `usagiusagi`.length;
enum long eleven   = `usagiusagiu`.length;
enum long twelve   = `usagiusagius`.length;
enum long thirteen = `usagiusagiusa`.length;
enum long fourteen = `usagiusagiusag`.length;
enum long fifteen  = `usagiusagiusagi`.length;

T add(T)(T a, T b) {
  return mixin(`a ` ~ cast(char)(two << four | eleven) ~ ` b`);
}
T mul(T)(T a, T b) {
  return mixin(`a ` ~ cast(char)(two << four | ten) ~ ` b`);
}
T mod(T)(T a, T b) {
  return mixin(`a ` ~ cast(char)(two << four | five) ~ ` b`);
}

void main() {
  for (string line; (line = readln) !is null; ) {
    const N = line.chomp.to!long;
    bool ans = (N >= two);
    foreach (d; two .. N) {
      if (mod(N, d) == zero) {
        ans = false;
      }
    }
    writeln(ans ? "YES" : "NO");
  }
}