Convert from obolos [Ancient Greece] to megatonne

Unit Definition (obolos [Ancient Greece])
The obolos [Ancient Greece] is a historic unit of weight or mass. The obol is a very small weight that originated as the weight of a tiny Greek coin. In ancient Greece the obolos was equal to 1/6 drachma, or roughly half a gram (8 grains).

Unit Definition (megatonne)
The megatonne is a metric unit of mass or weight equal to one million metric tons (tonnes), one teragram (Tg), or about 2.2046 billion pounds.