It was named after Austrian astronomer Karl Müller.

The rim of this crater is irregular and slightly oblong, with the long dimension oriented along a north–south axis.

Perhaps the most distinctive feature of this crater is the peculiar linear formation of small craters that starts at the southern edge of Müller's rim.

These follow a line to the northwest, tangential to the rim of Ptolemaeus.

By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Müller.