How to make android phone not reachable?

How to make android phone not reachable when someone calls me?
Answer #1
mr number
Answer #2
Take out the SIM!
Answer #3
Turn it off ?
davelerave replied: mr number
This is a good app
http://mrnumber.com/
Answer #4
https://market.android.com/details?id=fahrbot.apps.rootcallblocker.pro&hl=en
Answer #5
This Link will Surely Help you ! Don’t Forget to says Thanks !
(Android) Paid Market of 2012 -Maximum Apps/Games–Updated-
~Removed-lionden~
Answer #6
you could just put it in airplane mode?
if you just wanna block a specific person, then use one of the apps from above.