17 (seventeen) is the natural number following 16 and preceding 18. It is prime.
In speech, the numbers 17 and 70 are often confused as they sound similar. When carefully enunciated, they differ in which syllable is stressed: 17 /sɛvɨnˈtiːn/ vs 70 /ˈsɛvɨnti/. However, in dates such as 1789 or when contrasting numbers in the teens, such as 16, 17, 18, the stress shifts to the first syllable: 17 /ˈsɛvɨntiːn/.
The number 17 has wide significance in pure mathematics, as well as in applied sciences, law, music, religion, sports, and other cultural phenomena.
You are an adult at the age of 18. You become legally responsible for your actions without any responsibilty to your parents. You are legally seen as an adult in the eyes of the law - appear before adult courts, be called to serve on a jury, sue or be sued, vote in elections, become an organ donor, leave home without parental permission, get married without parental permission, apply for a passport without parental permission, ask to see your birth certificate if you are adopted, change your name, make a will, act as executor of a person's will, place a bet, have a tattoo, open a bank account in your name without a parent or guardian's signature
You can apply for loans and credit cards, apply for a mortgage, own a house or land, sign/enter into a binding contract, see an 18 rated film in the cinema, buy or rent an 18 DVD or video, buy fireworks, join any of the armed forces without the permission of your parent/guardian, go into a sex shop, pawn things at a pawn shop.