Hola,
Leyendo la pagina sagrada de MySQL
http://www.mysql.com/doc/en/Legal_names.html :
Cita: In MySQL versions prior to 3.23.6, the name rules are as follows:
...
A name may start with any character that is legal in a name. In particular, a name may start with a digit (this differs from many other database systems!). However, a name cannot consist only of digits.
Saludos.