class Ideone {
 
  public static void main(String[] args) {
    final long seconds = 1637208584L;
    final long microOfSecond = 795307;
    final long sum = seconds + microOfSecond;
    final long micros = seconds * 1_000_000L + microOfSecond;
    System.out.println("seconds + micro_of_second:             " + (seconds + microOfSecond));
    System.out.println("sum:                                   " + sum);
    System.out.println("equal?:                                " + (sum == seconds + microOfSecond));
    System.out.println("seconds * 1_000_000 + micro_of_second: " + (seconds * 1_000_000 + microOfSecond));
    System.out.println("micros:                                " + micros);
  }
}

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