There is no built-in way to do that, sorry. However one possible solution would be an override plugin that replaces the qa_format_number function (from qa-include/app/format.php). You'd need to convert the number from the $number variable into your language and return the resulting string.
That function is used for most numbers that are displayed.
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July 15, 2020: Q2A 1.8.5 released!