Well, it is the mark of the beast; and if you take its mark and worship it (the beast), you go to hell. So, it's pretty bad. Also, the same number is mentioned several times in the Bible. I don't know what that means, but I don't think it is a coincidence. *14* Now the weight of gold that came to Solomon in one year was **six hundred threescore and six** talents of gold, *- 1 Kings 10:14 (KJV)* *13* Now the weight of gold that came to Solomon in one year was **six hundred and threescore and six** talents of gold; *- 2 Chronicles 9:13 (KJV)* *13* The children of Adonikam, **six hundred sixty and six**. *- Ezra 2:13 (KJV)* *18* Here is wisdom. Let him that hath understanding count the number of the beast: for it is the number of a man; and his number is **Six hundred threescore and six**. *- Revelation 13:18 (KJV)*