How to call in Paris

It should be a ten digit number. That may be the country code that is listed, which you won't need, while making calls within the country. All French numbers begin with zero. The prefix for Paris is 01, but for mobile numbers it's 06. Hope this helps!

Does the number start with 33? Maybe they've given you the number as it would be called from the U.S. (or a U.S. cell phone?)?

The extra three numbers are probably the country code for the USA (1) and for France (33). That's my guess. Well anyway, the ten digit number, as I gave to you will work within France.

If calling from the States it's 011-33-plus the number, but with no zero. For example, as stated above if you are in France, all Paris numbers begin with 01, while cell phones begin with 06. To call from the States, it would be 011-33-plus the number beginning with the 1 or the 6 (or 3 if for Bungundy, 4 for the Riviera, 2 for Brittany, etc), but no initial zero. In other words, if you are in Paris, you'd call: 01-11-22-33-44.
If you are calling from the States, it's: 011-33-111-22-33-44.

Thanks so much! very helpful!

It's a bit confusing at first, but just takes a bit of adjusting to get used it. Then it's pretty much something that's standard for you. That's the way I found it. Although, you forget these things when you go some time from traveling there or elsewhere abroad. You get used to it. In general on leisure I don't make that many calls. A few back home and others for restaurant ressies etc. Don't spend nearly the amount of time on the phone as I do in the USA. Just make calls when necessary.