A billionaire is someone who has at least a thousand times a million dollars, euros, or the currency of the given country (i.e. $1,000,000,000). In contrast, a billionaire in countries that use the long scale number naming system would be someone who has at least a million times a million units of currency (i.e. $1,000,000,000,000). There is no evidence that anyone on the planet has achieved the latter in either dollars or euros.
