<?php
$s = "levis 5° 501";
preg_match('~^(.*?)\s*(\d+)\D*$~s', $s, $matches); print_r($matches[1] . ": ". $matches[2]. PHP_EOL
);
PD9waHAKCiRzID0gImxldmlzIDXCsCA1MDEiOwpwcmVnX21hdGNoKCd+XiguKj8pXHMqKFxkKylcRCokfnMnLCAkcywgJG1hdGNoZXMpOwpwcmludF9yKCRtYXRjaGVzWzFdIC4gIjogIi4gJG1hdGNoZXNbMl0uIFBIUF9FT0wpOwpwcmludF9yKHByZWdfc3BsaXQoJ35ccyooPz1ccypcZCtcRCokKX4nLCAkcywgMikpOw==