There are about 4000 and odd sutras are there by Panini. The doubt is why so many sutras.  But can you guess how many words that can be generated out of a धातु:?
1)1 धातुः can become 5 धातव:
(धातु+णिच्,+सन्+(सन्+णिच्)+(णिच्+सन्)
2) 5धातवः×10×9लकाराः5×90=450
3) 5धातवः
×12कृत्प्रत्ययाः×21सुप्--------=1260
×5 त्वा,तुम्–––--------------------=     10
4)60कृत् ×5(क्यच् etc)=
                          300×90=.  27000
5)300 नाम×12कृत्×21सुप्  = 75600
6) अव्ययकृत्--300×2          =     600
                                             ----------
1धातुः can generate        1,04,920

And we have circa 2000 Dhatu

And possible words
 2000×1,04,920!!
And Panini created just 4000 sutras for their creation!! Great!!
Courtesy:Vyomalabs
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