Cetus is a constellation, not a star. It is a large constellation in the Southern Celestial Hemisphere and is home to a number of notable stars, including:

* Mira: A red giant star that is a famous variable star, meaning its brightness changes over time.

* Menkar: A red giant star and the brightest star in Cetus.

* Diphda: A white giant star that is the second brightest star in Cetus.

So, Cetus doesn't have a specific number of stars, but it contains many stars, including those mentioned above.