How many protons neutrons electrons does Cs have?

Cesium (Cs) has 55 protons, as indicated by its atomic number. In a neutral atom, it also has 55 electrons. The number of neutrons can be determined by subtracting the atomic number from the Atomic Mass; the most common isotope of cesium has approximately 78 neutrons (55 protons + 78 neutrons = 133 atomic mass).