Recently I went to the store and when I asked for a 400W 6500K bulb they offered me this;

Philips E40 HPI-T 400W

The color temperature is 4000K i think, not really sure.

Is this a potential bulb for a proyector?, what else can I search for? , I want to try finding a good bulb here in my country, because buying it online from the lumen-store can be a little expensive for me.

Thanks.

It should work fine. You might want to try for something with a higher CRI (85+), though. Here's the Best Bulbs Chart.
You don't say what size LCD you're going to be using, but if it's smaller than 15", you might want to consider a double-ended lamp.

Google: Philips E40 HPI-T 400W

HPI-T PLUS 400W/643 E40 SLV

Thank you very much!

I want to use a 15 lcd but I didn`t start the search for one yet.

I see that the CRI and the colour temp are important, but, what about the wattage?

My personal opinion is that the wattage depends on your throw. If your throw is only going to be 10 feet or less, go with a 150W or 250W. I'll probably switch to 250W when I burn my present lamp out. Maybe before.
If you've got a longer throw, you'll want a brighter bulb. But you also have to factor in the heat that a brighter bulb puts out. It's not so detrimental to the internals of the projector (as long as you have good air flow), but the heat exiting the enclosure can really warm up a room.

I don't want a projection bigger than 100" so 10 feets or less are fine, maybe I should go for a 250W bulb with the correct CRI and 6500K if is brighter enough.

Thanks.