There are around 400 million native Spanish speakers worldwide, making it the world's 2nd or 3rd most common language, depending on which report you believe.

15% (44 million people) of the Total US Population is Hispanic and speak Spanish at home. 

The US is the 3rd largest Spanish speaking market on the internet after Mexico and Spain.

I own thousands of single word and category killer domains - listed below is a sample of the domains in the Spanish Geo portfolio - see also the Spanish Medical list and the Spanish Geo list. The domains themselves are linked in bold & a translation is listed below each.