We counted to 15 in Italian, let's keep going!
16 sedici - sounds like say-dee-chee /?/
17 diciassette - sounds like dee-cha-set-tay /?/
18 diciotto - sounds like dee-chee-oh-toh /?/
19 diciannove - sounds like dee-chee-ah-noh-vay /?/
20 venti - sounds like vay-n-tee /?/
(from: wikipedia - accademia della crusca)
German:
sechzehn, siebzehn, achtzehn, neunzehn, zwanzig
Spanish:
dieciséis, diecisiete, dieciocho, diecinueve, veinte
French:
seize, dix-sept, dix-huit, dix-neuf, vingt