911 is the North American standard. I was thinking in case something happens and one were to panic that it'd be good to know if dialling 911, in other countries where it is not the primary emergency number, is still set up to go through to emergency services.
The closest thing there is to a standard international emergency number is 112, which is used in 81 countries, including in the US by some carriers and in Canada on mobile phones. 911 does not seem to be in significant use outside of the US and Canada.
If you take a look at this pdf, you'll find a list of the emergency numbers of 243 countries and principalities, for Ambulance, Fire and police.
If you tally the number of countries where 911 is an emergency number you'll get 38 countries/principalities other than the US that use this number.
It's pretty much a non-issue nowadays. 911 and 112 aren't treated as phone numbers by mobile phones. That is to say, they're not sent as number strings to be recognized by the central phone switch. Instead, the phone itself recognizes the number and initiates a special emergency call.
The benefit of this method is that the call can be treated as a priority call immediately, so radio channels can be freed straight away.
Yes. At least on Brazil, you can call 911 or 112 and it will be routed to their national emergency call system seamless, without requiring you do to anything.
I don't know for others countries but I think this is pretty standard everywhere, since most of the world either use 911 or 112, and this allow tourists to quickly call the the police or ambulance/etc without previously knowing which number a specific country uses.