Welcome to the first Internet Treasure Hunt! Enjoy the search, your prize is just on the other end!

To start, a simple riddle will lead you on your way. Each of the clues leads to a letter or a number.

My first stand tall, ahead of 25 of its brethren,

My second's head is above a body so straight,

My third and fourth, the year of the biggest Nuclear disaster in history,

My fifth is twice of you, not me

Geniuses and mathematicians constantly search for my last.

Add them, in order, to:

http://tiny.cc/

And be on your way to the next hint!