Internal resister for ADG465

Dir Sir/Madam,

I have some questions for ADG465BRTZ.

Does the following 2 functions same as MUX ADG508F and ADG509F?

1)Over voltage protection
2)When power off, the internal MOSFET D-S keep off

When ADG465 is out the following conditions, what is the internal resistance?

case-1:input signal=non(0V)
case-2:input signal=5Vdc

When the supply power is off, what is the internal resistance?
I think that the internal resistance show over 10Mohm.

Please explain these.

Thanks Kaos