The number of whole microseconds spanned by this Duration.
The returned value can be greater than 999999. For example, a duration of three seconds, 125 milliseconds and 369 microseconds has 3125369 microseconds.
const duration = Duration(seconds: 3, milliseconds: 125, microseconds: 369); print(duration.inMicroseconds); // 3125369
int get inMicroseconds => _duration;