I couldn't find an online table of exponents for sporadic groups, so I used GAP to produce one:
```
[ [ "M11", 1320 ], 
  [ "M12", 1320 ], 
  [ "J1", 43890 ], 
  [ "M22", 9240 ], 
  [ "J2", 840 ], 
  [ "M23", 212520 ], 
  [ "HS", 9240 ], 
  [ "J3", 116280 ], 
  [ "M24", 212520 ], 
  [ "McL", 27720 ], 
  [ "He", 14280 ], 
  [ "Ru", 633360 ], 
  [ "Suz", 360360 ], 
  [ "ON", 10884720 ], 
  [ "Co3", 637560 ], 
  [ "Co2", 1275120 ], 
  [ "Fi22", 720720 ], 
  [ "HN", 2633400 ],
  [ "Ly", 10651271400 ], 
  [ "Th", 57886920 ], 
  [ "Fi23", 845404560 ], 
  [ "Co1", 16576560 ], 
  [ "J4", 607938537360 ], 
  [ "F3+", 24516732240 ], 
  [ "B", 234033344344800 ], 
  [ "M", 1165654792878376600800 ] ]
```