Highest C on a 61 key keyboard?

[Myst and rain]

Hi,

I was hoping anyone could clarify/confirm the following:

I've read that 'Middle C' is 261.63 Hz, right? Which is the lowest C you can play on a 6 string guitar? So would that mean that the highest note on a 61 key keyboard, is the C that can be played on the 20th position on the high E string of a guitar?

I've read a lot about this. But I'm still not sure. lol

Myst