"This title was written on her forehead: MYSTERY BABYLON THE GREAT THE MOTHER OF PROSTITUTES AND OF THE ABOMINATIONS OF THE EARTH." (17:5). In Ezekiel 16:14-18* unfaithful Israel is called a harlot, in Revelation chapter 17 the apostate church is called a harlot. So we have two women and two cities: the Harlot in Babylon and the Lamb's Wife in New Jerusalem. God's People are called the Lamb's Wife (19:7, 21:2 & 9).
Note: The wilderness or desert (17:3) is where God's People fled (12:6 & 14). So is this passage looking at the situation from the viewpoint of God's People? Or, are the woman and beast now in the location where God's People are (were) on earth?
"...The seven heads are seven hills on which the woman sits.** They are also seven kings." (17:9). The five world powers that have fallen are believed to be: Egypt, Assyria, Babylon, Persia and Greece. Rome was a world power at the time the book of Revelation was written. Some believe Papal Rome maybe the seventh, which dominated the world for about 1600 years -- from 200AD to 1800AD.*** "The beast who once was, and now is not, is an eighth king. He belongs to the seven and is going to his destruction." (17:11). It seems the beast will have characteristics similar to the previous world powers.
"The ten horns you saw are ten kings who have not received a kingdom, but who for one hour will receive authority as kings along with the beast." (17:12). Is this one literal hour, a figurative hour (perhaps a short period of time), an hour as God measures time (41.7 years), or does it mean immediately (like in Daniel 3:6,15; 4:33; 5:5)? "They have one purpose and will give their power and their authority to the beast." (17:13). Note the vision of beasts in Daniel chapter 7. It is important to note here that it is the beast that "belongs" to the previous world powers. It does not say the kings are related to the previous world powers! "They will make war against the Lamb, but the Lamb will overcome them..." (17:14).
What a turn of events! The prostitute seduced people (17:2) with her charms (17:4) and devoured people (17:6), but now: "The beast and the ten horns you saw will hate the prostitute. They will bring her to ruin and leave her naked; they will eat her flesh and burn her with fire." (17:16). The apostate church is ruined!
*Also note chapter 23 of Ezekiel.
**"...great prostitute, who sits on many waters." (17:1). This probably means she sits on the people of the earth. In Genesis 1:1 God's spirit hovered over the waters, then in 1:6-8 God separated the waters -- those above where called sky and in 1:9-10 those gathered together below were called seas. "...The waters you saw, where the prostitute sits, are peoples, multitudes, nations and languages." (17:15). "With her the kings of the earth committed adultery and the inhabitants of the earth were intoxicated with the wine of her adulteries." (17:2). "...a woman sitting on a scarlet beast..." (17:3). The woman seduced kings and the inhabitants of the earth into sin.
***"The Popes of Rome were the heirs and successors of the Caesars of Rome. The Vatican is where the Palace of the Caesars was. The Popes have claimed all the authority the Caesars claimed, and more." (Halley's Bible Handbook).
Note: The beast does not seem to be a flesh & blood personage. The beast seems to be a spirit that enters the world through people. And gives these people beastly characteristics, qualities and traits.