2…..”And the weight of the gold that came to Sol′o·mon in one year amounted to six hundred and sixty-six talents of gold,” ~2 Chronicles 9:13

3…..”the sons of Ad·o·ni′kam, six hundred and sixty-six;” ~Ezra 2:13

4…..”Here is where wisdom comes in: Let the one that has intelligence calculate the number of the wild beast, for it is a man’s number; and its number is six hundred and sixty-six.” ~Revelation 13:18

4 times the number six hundred and sixty six is mentioned in the Bible.

(there is one more use for the actual number but that is just for the index)

not that much the only time i saw it was in revealtions