Is there a way of "Barring" certain numbers from dialing out on a trunk?

The company I work for used 18866 for outgoing calls but now they have discontinued that service but people are still using it.
So I want to Bar 18866 from dialing out? Is this Possible?

You can set up LCR on the system and use the TOLL ALLOW, TOLL DENY tables.

Is 18866 an access code?]
You can set up toll restriction to deny that number being dialled or if you are using LCR you could delete it if someone dialled it.

you can use MMC 702 to deny the number and use MMC 301 for cos to ext no