If you want it to display the value correctly you can raise it to the
third power, then by the one third power.

i.e.  =((850*77.1)^3)^(1/3)

and it will display 65535.

you could also use this as just a value check on an existing output
cell.

i.e. =((A1)^3)^(1/3)

that way you could reference it only when you think there is a
problem, and you won't have as much clutter in one cell.

I don't know why it works, nor do I understand half of what many of
you are talking about, but I do know this works in Excel 2007 and
because it's using an odd power it retains +/-.