Unless you've been abandoned on a desert island for the last decade, you'll know that Siri is Apple's very own digital personal assistant, ready to answer whenever you call.
As the years have gone on, iPhone users have discovered nifty little tricks that Siri can pull off that you may not have known about.
One such feature is when you say 17 to Siri.
So what happens when you say 17 to Siri?
Well, if you haven't already tried it, you'll be fascinated to know that saying 17 to Siri actually phones the emergency services, handy if you're in a bit of a pickle.
If you have tried it, we're very sorry.
Since this feature has been discovered it's obviously been used as a prank quite frequently.
The reason for Siri phoning the emergency services is because 17 is the emergency phone number in several countries.
It's a handy feature if you're abroad and you don't know the emergency number of the country you're in as Siri will contact the correct one for you.
The feature also works if you say 999 to Siri, the emergency number for the UK.
But obviously, we don't recommend phoning the emergency services unless it's absolutely vital.
What countries have 17 as their emergency number?
While 999 is the number of choice here in the UK, 17 is a popular number in many African countries including Burkina Faso, Chad, Mali, Niger and Senegal.
Most countries across the world use a three digit number for their emergency contact number, but not in the case of the countries above.
While 17 is a popular number in Africa, arguably the most popular emergency number in the world is 112, which is used by most countries across Europe and India.
Hopefully, you won't need to use them but it's always handy to know.
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