Meaning of "number of atoms"

Materials Project
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Could anybody explain me the meaning of the data point “number of atoms” that is shown for any material on the material project website? I thought that it was supossed to tell the number of atoms per unit cell but it doesn’t make any sense for me in many cases. For instance, TaC (mp-1086: TaC (Cubic, Fm-3m, 225)) exihibits a fcc crystal structure [Fm3̅m] and, thus, should feature 4 atoms per unit cell. However, “number of atoms” on the website says that it’s 8.

What am I missing?

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TaC has a NaCl-type crystal structure which allows addiotional atoms on the octahedral hole: https://chemed.chem.purdue.edu/genchem/topicreview/bp/ch13/unitcell.php

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