In the past I was ten to the power of four, but now I can be less or I can be more. Some people would say that as a noun I'm improper, but noun before adjective, in that form I first prospered.

Turn me on my side and I am everything. Cut me in half and I am nothing.

You can buy me, or make me, but you can never get more of me; You can kill me, but you'll still die while I continue on; What am I?

I am an odd number, and in my prime. But, most of me is even.

I am always ahead but never seen, I'm promised to all,yet belong to none You can chase me but never reach me, For once I arrive, I am already gone