How many protons, neutrons and electrons are there in one atom of this radon isotope?

image is an isotope of noble gas, radon. How many protons, neutrons and electrons are there in one atom of this radon isotope?

Answer:
Atomic number of radon = 86
The number of protons = 86
The number of electrons = Number of protons
=86
Number of neutrons = Atomic mass - Atomic number
= 222-86
= 136