The magic number right now would be 12 points.
As of now, the Habs have 7 games left and have 86 points.
http://www.tsn.ca/nhl/standings/
Rank Team GP W L OT PTS
8 Montreal 75 38 27 10 86
9 Florida 76 37 28 11 85
10 Buffalo 75 37 30 8 82
Assuming Buffalo and Florida each win the rest of their games, they would both have 96 and 97 points respectively.
That means, the Habs basically need 98 points to make the playoffs, so another 12 more as you said. Obviously, this number will change since this is all based on the premise that Florida wins all the rest of their games.