The Number 685: Properties and MeaningsPrime Factors of 685=5x137.
685 is a 17-gonal Number.
685 is a 70-gonal Number.
685 is a Centered Square Number.
685 is a Centered 19-gonal Number.
The Year 685 ADIn the year 685 AD the battle of Nechtansmere proved to be an overwhelming victory for the Pictish King Bridei over the expansionist Angles from Lothian and Northumbria and help to define the territory which would in time be called Scotland.
In the year 685 AD it was decreed in Nara that every household should have a Buddhist family shrine.
In the year 685 AD: Tang support for Buddhism in China.