What if I never use my EIN number?

If I never use my EIN number, what are the potential consequences? Is it possible for my business to function smoothly without it? Will it affect my tax obligations or other legal responsibilities? Should I still keep it on record in case I need it in the future? And what if I lose track of it and forget I even have one - how can I retrieve it if I need to? As a business owner, it's important to stay on top of these things, but I'm curious to know if an EIN is truly necessary for my operations.