Yes, it’s true. According to the Christian scriptures, 666 is the number of "the Beast." But the way people have carried on about it, one would think it were something like walking under a ladder. The number is a descriptor, not a superstitious talisman or something.

What the Scriptures say about Ol’ Six-sixty-six is this: "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). The number refers to a person, a specific person. The number just happens to be the numerical equivalent of Nero Caesar; so maybe it refers to him—depending on your eschatology. Maybe it refers to some future person, or some present person who just hasn’t been revealed for who he is. Maybe he’s a mythical person. Whatever and whoever he is, or may be, the number refers to him. But it doesn’t refer to anything and everything that is evil. The number itself isn’t going to bring you bad lack.
There is no magic, evil or otherwise, in the number 666. Nothing bad is going to happen to you because you live, as I did as a child, in a zip code whose last three digits are 666. (That’s right I lived in zip code nn666. I have lived to tell about it.)

If anything bad happens on 060606, it won’t be because it’s 060606. It will happen because bad stuff happens. When Job said, "Man is born to trouble as sparks fly upward (5.7)" he asserted a general principle about the human experience: as a general rule, daily, we will experience "trouble." Jesus told his disciples that there is in this world "tribulation" (John 16.33) as a matter of course.

In this life we experience good things and bad things. It has nothing to do with three digit numbers, black cats, ladders, broken mirrors, or cracks in the sidewalk . It is simply the way of things.

060606 is nothing more than the sixth day of the sixth month of the seventh year of the twenty-first century. That is nothing near the same as six hundred sixty-six. Think about it.
Look around the world. It’s another day of upward flying sparks. Deal with it.

Besides, why worry about the devil? Jesus can take him. He already has done.