The imminent release of Thr3e got me thinking about movie titles with numbers in them (besides sequels 
). A start:
1: One Flew Over a Cuckoo’s Nest
2: Lock, Stock and Two Smoking Barrels
3: Thr3e; Three Men and a Baby
7: Se7en; The Seven-Year Itch
9: The Ninth Gate
28: 28 Days; 28 Days Later
39: The 39 Steps
More, please! (Cardinal and ordinal numbers OK.)
I did this, out of curiousity, quite a while bacvk. If you go through the iMDB you can find plenty of flicks with simply number names, especially among small and indie films. I never tried to see how high I could go.
Without resorting to iMDB, and only using mahjor releases, I can still get:
**The One
Five
Seven
10**
Not to mention $
Six Graves to Cairo
Seven Brides for Seven Brothers
Sixteen Candles
The 400 Blows
2001: A Space Odyssey
3 Women
12 Monkeys
The Magnificent Seven
The Third Man
Four Weddings and a Funeral
The Fifth Element
The Fighting 69th
Off the top of my head from my collection:
The 40 Year-Old Virgin
1900
20 Million Miles to Earth
One Million Years BC
20,000 Leagues Under the Sea
8 1/2
The 400 Blows
12:01
and many more, I’m sure. But I have to work.
That’s what I was trying to do… 
Three Kings
Seven Brides for Seven Brothers
Twelve Angry Men
Pi
Eight Men Out
Two for the Seesaw
Eight Crazy Nights
Three on a Match
The Unholy Three
Seven
8 mm
9 & 1/2 Weeks
10 (or ten)
Oceans 11
12 monkeys
Friday The 13th pt 1 2 3 etc etc
There’s this Fantastic movie about the number Four. I can’t remember the title, though.
Okay, so it wasn’t really all that fantastic.
The Big Red One
Two Lane Blacktop
Waterhole #3
The Four Feathers
Five Easy Pieces
The Sixth Sense
The Seven Samurai
Hard Eight
9 to 5 (a twofer!)
Ten Little Indians
Four Rooms
200 Cigarettes
13 Ghosts
8 Heads in a Duffel Bag
So far, we’ve managed 1 through 13
1: One Flew Over a Cuckoo’s Nest
2: Lock, Stock and Two Smoking Barrels
3: Thr3e; Three Men and a Baby
Π: Pi
4: Four Rooms
5: Five Easy Pieces
6: Six Graves to Cairo
7: Se7en; The Seven-Year Itch
8: 8mm
8½: 8½
9: The Ninth Gate
10: Ten Little Indians
11: Ocean’s 11
12: 12 Monkeys
13: 13 Ghosts
14:
15:
16: Sixteen Candles
17:
18:
19:
20:
I’ll add
0: Suspect Zero
12 Angry Men
The 10,000 Fingers of Doctor T
Five Weeks in a Balloon
Around the world in 80 Days
8 Women
10
The 24th Day
25th Hour
29th and Gay
54
'68
1969
Ocean’s 12
Fahrenheit 451
From Noon until 3
Force 10 from Navarrone
The 13th Warrior
Friday the 13th
The 12 Chairs