Import the data as it is found in Excel and use Replace Field Contents with the calculation option to move data from the combined address text field into separate fields for each part of the address.
Map this column to a global text field. Set up the separate address fields as auto-enter calculations that extract the correct text from this field. When you import, be sure to click the check box for enabling auto-enter options during import.
The calculation for street number might be:
LeftWords ( AddressField ; 1 )
The one for the rest of the text might be:
RightWords ( AddressField ; WordCount ( AddressField ) - 1 )
these calculations can be used in either option, but assume a consistent data entry format used in entering the data that you are importing. If the data is not in a consistent format, it may not be possible to come up with calculations that automatically parse every possible address into the separate fields.