The note was written on the stationery of the Imperial Hotel in Tokyo.
Einstein told the hotel worker that if he was lucky, the notes would one day become valuable.
Einstein's statement was confirmed 100 years later and a nephew of the hotel worker's brother called the auction house to put the paper up for sale.
The buyer who conducted the operation was not disclosed via the Internet.
The auction also sold a second remark to Einstein saying "where there is will, there is a way"
At an auction today in Jerusalem for $ 1.56 million.
The seller is a resident of the German city of Hamburg and a close associate of the hotel owner's observation.