A math riddle has been printed on many images:
 
Q: Are monsters good at math?
A: No, unless you Count Dracula.
 
Forms of the joke have been cited in print since at least 2001.
 
   
Wikipedia: Dracula 
Dracula is an 1897 Gothic horror novel by Irish author Bram Stoker. It introduced the character of Count Dracula, and established many conventions of subsequent vampire fantasy. The novel tells the story of Dracula’s attempt to move from Transylvania to England so that he may find new blood and spread the undead curse, and of the battle between Dracula and a small group of men and a woman led by Professor Abraham Van Helsing.
 
Google Books
Super Silly School Jokes
By Gene Perret, Joseph Rosenbloom, Meridith Berk and Toni Vavrus
Illustrated by Sanford Hoffman
New York, NY: Sterling Publishing Company, Inc.
2001  
Pg. 50:
What monster is best at math?
Count Dracula.
   
Google Books
The World’s Funniest Monster Jokes for Kids
By Guy Campbell, Mark Devins and Paul Moran
London, UK: Egmont
2003
Pg. 40
What did the teacher say to Dracula after he failed his maths test?
Can’t you count, Dracula?
 
Twitter 
Vera Marques
@_Veerraa
How many monster’s are good at math? None, unless you Count Dracula. #childrenjokebook
11:48 AM - 13 Oct 2012
   
Twitter
Miss Lynch’s Class
@mramathletes
How many monsters are good at math? None, unless you Count Dracula! Have a Mathletic day today Algebros!
7:24 AM - 15 Oct 2015
 
Twitter
Cynthia Reeg
@cynthiareeg
Monster humor for #Halloween!
Which vampire is really good at math?
COUNT DRACULA!
#monsters #jokes
11:15 AM - 26 Oct 2015
 
Twitter   
7 Generation Games
@7GenGames
Today’s #dailymathjoke is: How many monsters are good at math? - A: None, unless you Count Dracula! @LaffGaff #joke #math #dracula
12:18 PM - 25 May 2016
 
Reddit—Jokes
Posted by u/TheeKirkman March 26, 2018
Are monsters good at math?
No, unless you Count Dracula
 
Reddit—Dadjokes
Posted by u/AlexDawesome October 23, 2018
Are monsters good at math?
Only if you Count Dracula.
0siris469
I heard he was a lot better in art class. He did draw a lot of blood…
 
Twitter
Sam Sheafer
@grooster
Dad Joke: How many monsters are good at math?
None, unless you count dracula 😊
1:28 PM - 29 Oct 2018
 
Twitter
BestOfferZone
@BestOfferZone1
Q. Are any Halloween monsters good at math?
A. No—unless you Count Dracula!
12:36 PM - 5 May 2019