Is That A Big Number?

If Duration of Pandyan Empire (South India) (1,850 y) was a standard unit ...

Duration of Mali Empire (375 y)...more would be 1/5 of Duration of Pandyan Empire (South India)

Period of Halley's Comet's orbit (75.3 y)...more would be 1/25 of Duration of Pandyan Empire (South India)

Period of Ceres's orbit (4.6 y)...more would be 1/400 of Duration of Pandyan Empire (South India)

Period of Mars's orbit (1.88 y)...more would be 1/1000 of Duration of Pandyan Empire (South India)

Yes, there's now a book based on these numbers. Oxford University Press: July 2018.