That's how I remembered 2147483647:
- 214 - because 2.14 is approximately pi-1
- 48 = 6*8
- 64 = 8*8
Write these horizontally:
214_48_64_
and insert:
^ ^ ^
7 3 7 - which is Boeing's airliner jet (thanks, sgorozco)
Now you've got 2147483647.
Hope this helps at least a bit.
