In terms of NPI assignment, a sole proprietor is an Entity type 1 Individual and is eligible for only one NPI the sole proprietorship business is not eligible for its own NPI.
The First, Middle, Last and Credential s fields allow the following special characters: ampersand, apostrophe, colon, comma, forward slash, hyphen, left and right parentheses, period, pound sign, quotation mark, and semi-colon.