What is that means?

Let me be the first to put some serious effort into responding to this. The number of the beast is 666. In this day and age we do not generally use letters from our alphabet to represent numbers. Back then things were different. Both the Romans and the Greeks used letters to represent numbers. Ever had to learn to use Roman numerals in school? That's what I'm talking about. Basically that means you can "add" the letters in a name and come up with a total. Turns out the roman name Romulus adds up to 666. In Greek Lateinos also adds up to 666. At the time the book of Revelation was written the Christian church was being severely persecuted by the Roman Empire. This code is a very clear reference to the Roman Empire and the Roman Emperor. It has since been interpreted to mean a whole lot more but whole books can and have been written on the subject. This information is readily available through other sources on the Internet.

This number has always been related to Satan, although i have no idea why. i even read some explanations why this number was treated as the number of Antichrist or the devil. But nothing made sense or really explained it. I'll also just wait for the other responses here.

It is the number that comes right after 665 and just before 667.

In the Apostle's time the Hebrew letters of Romiith were known to add up to 666. Lateinos is not used in the Greek New Testament, where the word is Romaios. However, Irenaeus (pupil of Polycarp, who was a pupil of the Apostle John) suggests this word in his writings (which does not mean that he got it from Polycarp, or if he did, that Polycarp got it from the Apostle). The Greek numerals in Lateinos also add up to 666. Then imperial Rome fell, but out of its ruins arose the Roman Catholic Church and its Pope (like the Roman Emperor, in his successions) making increased claims. In 1701, Robert Fleming published The Rise and Fall of Papal Rome, showing, amongst other things, that the Latin numerals in the title VICARIVS FILII DEI, ascribed to the Pope in the Vatican-approved Donation of Constantine (now admitted by absolutely everyone to be a forgery, but Papal approval of a document, once given, can never be withdrawn - Infallibility and all that) also add up to 666. There are other words and phrases connected with the Pope, whose Latin numerals also add up to 666. The Seventh Day Adventists are not fully Christian, but on the matter of the Pope they have done their homework well. A better source about the Pope, excluding considerations of 666, but majoring on 2Thessalonians 2, is Bishop Christopher Wordsworth's Is the Papacy predicted by St. Paul?.

I ran across a site the other day about how Greek letters are also uses as numbers. And if you have a word that the number-letter show up, you could add the numbers up and come up with a sum, i.e. 666. So there are many words in greek that can be add up 666.

Evil reasoning, evil feelings, and evil will.

I have heard that it is the number of satan. Which isn't a good number.

I don't care. In my Bible, it says "six-hundred, three-score & six." Who decided that 'score' was twenty? Anyway, they say that is 'the mark of the beast' which the AntiChrist worships, the mark the AntiChrist forces everyone to accept upon their wrist or forehead if they want to be able to buy or sell. I don't know if the AntiChrist- or the Beast-will be a person or a group or a technology or what, but I know that 'restriction to where only those with The Mark will be able to buy or sell' will work ... ... look at digital-phones (or whatever they're calling those little mobile gadgets nowadays). There are some bargains you can only get with coupons shown on your digital-phone. Those of us without digital-phones (including me ) do not have that 'power to buy or sell.' (I could speculate from that condition that the AntiChrist and/or Beast is the Internet and/or the wireless-industry! )

There's bound to be tons of imaginative speculation on 'why that exact number' etc., but that's not the point. The point is that (Scripture says) the mark will be 'the name of the Beast or the number of his name.' The people of G-d will be 'marked' too, by an angel. But Jesus doesn't ask us to pay any attention to this stuff if it gets in the way of serving Him. He tells us to 'watch,' but that's more to guard against anything hindering our service than -to KNOW anything. ("Eye has not seen- Nor has ear heard what G-d has ready for those who love Him.")

I'm not really prepared for this as I can't say that I've read revelations. Some bright spark said that in the future we would be known by the number stamped on our forehead and the number of the beast would be 666.

I don't know what these numbers mean , about your response about 3 persons will be in the last days , that is true , they are as they appear : Almahdi , Antichrist , Jesus who will kill the Antichrist to show that he is not the God ( Antichrist will claim that is God )

At a very young age , i already heard about this. They said it is an anti christ. If this happen then it is the end of the world. Long back have heard about this ,but to God's grace up to now , we are still around and a believer of God. 666 0r 777 what eve is the number , no worries it is just a number , we have a big and great God who will protect us.

well, I learn that in a movie that 666 is an evil number and evil sign... I still remember scene of that movie but I forgot the name...