Karsted Air Services is now in the final year of a project. The equipment originally cost $$21$ million, of which $100\%$ has been depreciated. Karsted can sell the used equipment today for $$7$ million, and its tax rate is $20\%.$ What is the equipment's after$-$tax salvage value? Write out your answer completely. For example, $13$ million should be entered as $13,000,000.$ Round your answer to the nearest dollar.