Native resistances delayed the progress of colonization. An example of this is the Pueblo revolt. As a result of the Pueblo revolt Spanish colonization slowed and the Native Americans were able to hold off the Spanish for a brief period of time,
1 million is 1 x 10^6
1 billion is 1 x 10^9
1 trillion is 1 x 10^12
So 12 trillion miles is 12 x 10^12 which converts to 1.2 x 10^1 x 10^12 = 1.2 x 10^13