'drush field-create' with type INTEGER from command line? drupal (ver 7.22) | drush (ver 6)
for an integer field type, try this : 

drush field-create user streetnumber, number_integer, number_textfield


Or : 

drush field-create user streetnumber, number_integer


(because you can ommit the widget type and the default one will be used). 

If you are looking for the name of another field type, create the field in the admin panel, then look in your database, in table field_config, you will find it in the type column.