* <p>To test larger numbers, use {@link BigInteger#isProbablePrime}.
   *
   * @throws IllegalArgumentException if {@code n} is negative
   * @since 20.0
   */
  @GwtIncompatible // TODO
  public static boolean isPrime(long n) {
    if (n < 2) {
      checkNonNegative("n", n);
      return false;
    }
    if (n < 66) {
      // Encode all primes less than 66 into mask without 0 and 1.
      long mask =