Fax is short for facsimile. Fax number and facsimile number has numbering format the same with standard phone number. Internet fax number on the other hand is a combination of phone number and...
Yes - there is an infinite number of such numbers. Just take the counting numbers (1,2,3,4, etc...) and put them to the power of 6 (i.e. multiply it by itself 6 times). The sequence of such numbers...