Decode 2017 saved video datetime stamp/code?

I saved several Ring Pro video doorbell clips from both the app and website in fall 2017. I have no datetime stamp on the video itself, but do have a unique 19-digit number associated with each file saved. Examples:2017.09.02 - 6461287472267125339.mp4,2017.09.03 - 6461578108409078363.mp42017.09.04 - 6461939989468537435.mp42017.09.18 - 6467251936300753499.mp4I have tried various online datetime converters (Epoch time, time since year 0001, etc..), but nothing returns correct datetime.Does anyone know if these 19-digit numbers can be decoded into human-readable datetime or are they just unique IDs used in Ring's databases?