[1] Arp 251 is cataloged in the Atlas of Peculiar Galaxies,[2] which is a catalog of unusual galaxies put into groups based on purely morphological criteria.

Arp 251 belongs to the class of galaxies with signs of splitting.

It spans 30 arc-seconds in apparent view, which corresponds to a diameter of 170,000 light years.

The upper arm is disturbed, meaning that galaxy interaction may be present.

It has a larger angular size than the other galaxies making up Arp 251.