[5] NGC 1624-2 is a very massive, young, blue star no more than 4 million years old.

The luminosity class is uncertain because of the unusual spectrum; it is most commonly given as V (main sequence), but has also been given as I (supergiant).

[7] Analysis of its spectral energy distribution with CHORIZOS modelling yields an effective temperature of 35,000 K, a luminosity of 125,900 L☉ (105.1 L☉) and a radius of about 10 R☉.

However, this assumes that NGC 1624-2 is a normal star, while it is not, so it should only be taken as an indication of its true mass.

NGC 1624-2 is currently losing mass at a rate of 10−6.8 M☉/year, through a stellar wind with a terminal velocity of 2,875 km/s.