Generally any mantras should be recited 108 times (100+8; extra 8 counts are done as prayaschitta for any mistakes done during chanting), 1008 times etc.. But 10 is also a valid number.
In Mahanirvana Tantra's 7th chapter Lord Shiva says this:
O Gentle One! In all daily prayers recitation shouldbe done one thousand and eight or a hundred and eight or ten times (79). O Devi!
the Shudras and Samanyas may observe any of the rites proclaimed by
the Agamas, and by these they attain that which they desire (80). The
three times of performance (of Sandhya) are at sunrise, at noon, and
at sunset (81)
But when chanting is done for Purascharana then count should be N lac where N denotes the number of letters the mantra is made of. And in case of stotra recital usually the number of minimum chants is 3.