Sixteen
numeral
You have ten and six (not to be confused with six tens!). When you have ten and six, you have a total of sixteen.
じゅうろく
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well!
十六さいのたんじょうびにふじ山にのぼりました。
I climbed Mt. Fuji on my sixteenth birthday.
もう十六ねんもふじ山の入り口からうごかないアメリカ人がいます。
There is an American who hasn't moved away from the entrance of Mt. Fuji for 16 years.
わたしはえいえんの十六さいです。
I am forever sixteen.