It doesn't apply for two reasons: it is not addressing the days of creation at all; and it shows two very different time scales one million times apart in comparison to a single day. In the same way Moses, in Psalm 90, compares 1,000 years to 'yesterday' or 'a watch in the night' which depending on your references is either three or four hours. That's now three, if not four different relative comparisons for the length of a day. The point of both passages is that God's perception of time is not the same as ours, and He is not restricted in the dimension of time as we are.Why doesn't this apply?
2 Peter 3:8 But, beloved, be not ignorant of this one thing, that one day is with the Lord as a thousand years, and a thousand years as one day.
Consider this: is it reasonable to think that the sun stopped for about 1,000 years for Joshua? Is it reasonable to think that the Israelites marched around Jericho for 7,000 years? Is it reasonable to think that Jonah was in the great fish for 3,000 years? Of course not... so why do we question God's word when it says "For in six days, He made the heavens and the earth, the seas, and everything in them"?