Answer:
Alone I am 24th with a friend I am 20. Another friend and I am unclean.
In many hall ways you would stand if not with me in hand.
Although glory but not at my best. Power will fall to me when the man who made me dies.
I can't go left, I can't go right. I am forever stuck in a building over three stories high. What am I?
Some try to hide, some try to cheat, but time will show we always will meet.
It has no top or bottom, but it can hold flesh, bones, and blood all at the same time.