Meaning of the word "mass number" in English

What does "mass number" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

mass number

US /ˈmæs ˌnʌm.bɚ/
UK /ˈmæs ˌnʌm.bər/
"mass number" picture

Noun

the total number of protons and neutrons in the nucleus of an atom

Example:
The mass number of carbon-12 is twelve.
Isotopes of an element have the same atomic number but a different mass number.