Top ten most commonly spoken languages:

1. Mandarin
2. English
3. Hindustani
4. Spanish
5. Russian
6. Arabic
7. Bengali
8. Portuguese
9. Malay-Indonesian
10. French

This article has a breakdown by numbers. According to Wikipedia, there are still 900 Ottoman speakers left, but only 10 people in Russia still speak Ter Sami. Wonder what it sounds like, and what concept they have a word for that no one else does.

More about the Sami language and its dialects on You Tube.