We counted to 15 in Swahili, let's keep going!
16 kumi na sita - sounds like koo-mee nah see-tah 文A
17 kumi na saba - sounds like koo-mee nah sah-bah 文A
18 kumi na nane - sounds like koo-mee nah nah-nay 文A
19 kumi na tisa - sounds like koo-mee nah tee-sah 文A
20 ishirini - sounds like ee-she-ree-nee 文A
(from: wikipedia - swahili language)
Russian: шестнадцать (shestnadtsat'), семнадцать (semnadtsat'), восемнадцать (vosemnadtsat'), девятнадцать (devyatnadtsat'), двадцать (dvadtsat')
Norwegian: seksten, sytten, atten, nitten, tjue
Greek: δεκαέξι (dekaéxi), δεκαεπτά (dekaeptá), δεκαοχτώ (dekaochtó), δεκαεννέα (dekaennéa), είκοσι (eíkosi)
ASL: sixteen, seventeen, eighteen, nineteen, twenty
Italian: sedici, diciassette, diciotto, diciannove, venti
German: sechzehn, siebzehn, achtzehn, neunzehn, zwanzig
Spanish: dieciséis, diecisiete, dieciocho, diecinueve, veinte
French: seize, dix-sept, dix-huit, dix-neuf, vingt