Convert from gigameter to megaparsec

Unit Definition (gigameter)
The Gigameter (or Gigametre) a metric unit of distance equal to one million kilometers or about 621,371.2 miles. It is seldom used, but this unit would be a good yardstick for the inner Solar System: the distance from the earth to the sun is about 149.60 gigameters.

Unit Definition (megaparsec)
The parsec (symbol pc) is a unit of length used in astronomy. It stands for "parallax of one arc second", and is approximately 19,131,554,073,600 (19 trillion) miles.