There isn't A list, mainly, because anyone (everyone !) can change the color palette of every workbook... but, you can find out with a simple macro:
And by "number" I hope you mean the ColorIndex !
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<SPAN style="color:#00007F">Sub</SPAN> ShowColors()
<SPAN style="color:#00007F">Dim</SPAN> i <SPAN style="color:#00007F">As</SPAN> <SPAN style="color:#00007F">Long</SPAN>
Application.ScreenUpdating = <SPAN style="color:#00007F">False</SPAN>
<SPAN style="color:#00007F">For</SPAN> i = 1 <SPAN style="color:#00007F">To</SPAN> 56
Cells(i, 1).Value = i
Cells(i, 2).Interior.ColorIndex = i
<SPAN style="color:#00007F">Next</SPAN> i
Application.ScreenUpdating = <SPAN style="color:#00007F">True</SPAN>
<SPAN style="color:#00007F">End</SPAN> <SPAN style="color:#00007F">Sub</SPAN>
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