Einstein was a theoretical physicist, as well as an inventor. He did come up with one particular formula that you may have heard of...E=MC2 (E=MC squared). He did a lot of that kind of thing but this was his most famous, which he presented in 1905.
He co-invented a type of refrigerator with no moving parts; patent number 1781541. An electromagnetic pump; patent number GB303065, a self adjusting camera; patent number US2058562, and a sound replication device; patent number DE590783. Along with dozens of other patents worldwide. You may look up the patent numbers to see when they were filed.
Albert Einstein did not invent mathematics.
No, Albert Einstein did not invent repeating decimals.
Albert Einstein did not invent any mathematical inventions.
he was 27 years old
He did not invent the calculator- but was a professor of mathematics. See the link at the bottom of this page for information on him.