What is special that Hashem counts the stars? Astronomers agree that there are 1098!
Radak citing R. Avraham ben R. Chiya: The big stars that illuminate on the land, they have a number. Small stars that do not illuminate 1 on the land, they are many; man cannot see them, and all the more so he cannot count them 2 . The latter were created to rule over the land, and not to illuminate - "v'Limshol ba'Yom uva'Laylah" (Bereishis 1:18). Also the visible stars, a star can appear like one, but really, it is many.
Pesachim 2a implies that there are stars that do not illuminate. (PF)
Radak: Also, we find that Hashem told Avraham "u'Sfor ha'Kochavim Im Tuchal Lispor Osam" (Bereishis 15:5). And it says "ha'Yesh Mispar li'Gdudav" (Iyov 25:3)!
What is the significance of calling names to all the stars?
Radak: Hashem created all of them with a number known to Him. Each has a name proper for it, based on why it was created. Each star has authority over a species of creations below - there is no grass below without a Mazal above that hits it, and tells it to grow (Bereishis Rabah 10:6).
Malbim: Conduct over the nations is via the Ma'arachah. The stars are fixed in number; it cannot be increase or decreased. And they are fixed in their hearts actions. Each has a name, i.e. its power - this one influences life, and this one wealth, and this one destruction