Paramatma(n)(Supreme soul) means the creator of all souls.  The description of the word parama is that there is nothing beyond it.  atman means soul .

Is there one or more of the Paramatma? 
Paramatma(n) is only one. 

However, who are the gods and what are they called? 
The gods are called Devatmas.  They have divine powers and perform their duties according to the law of creation.

What are humans and other creatures called?  Humans are called the Jeevatma.