Dear Student,
Although these two differ in physical properties there are some properties which these two resemble just like each other and that property is diffraction.
Each raindrop reflects the sun. Due to dispersion different colors dominate in different directions. This is the reason behind the formation of the rainbow in the sky.
Prism, on the other hand, does the same thing i.e, dispersion of light but we usually do this dispersion activity in our lab.
Regards