It could be actually even smaller - I've recently found out about NAC (aka Universal Address) which store the geographical positions in the form of two strings of letters and digits (e.g. H5Q2R R48PF - Eiffel Tower). The brilliant thing about this geocoding system is that it is almost indefinitely scalable - the more precision you need, the more digits/letters you use as each character represents a fraction of the area described by the previous characters (i.e. H5Q2R is contained within H5Q2, which is contained in H5Q and so on.)
In a real-life situations you wouldn't need more than 10 characters (as 5+5 characters give you the precision of ~3 ft).