Who is Lord of Lords?

Deuteronomy 10:17 NWT

For Jehovah your God is the God of gods and the Lord of lords, the God great, mighty, and awe-inspiring, who treats none with partiality and does not accept a bribe.

Psalm 136:1-3 NWT

Give thanks to Jehovah, for he is good;
His loyal love endures forever.
Give thanks to the God of gods,
For his loyal love endures forever.
Give thanks to the Lord of lords,
For his loyal love endures forever.

Who is the "God of gods and Lord of lords"?
Revelation 17:14 NWT

These will battle with the Lamb, but because he is Lord of lords and King of kings, the Lamb will conquer them. Also, those with him who are called and chosen and faithful will do so.”

Revelation 19:12-16 NWT

His eyes are a fiery flame, and on his head are many diadems. He has a name written that no one knows but he himself, and he is clothed with an outer garment stained with blood, and he is called by the name The Word of God. Also, the armies in heaven were following him on white horses, and they were clothed in white, clean, fine linen. And out of his mouth protrudes a sharp, long sword with which to strike the nations, and he will shepherd them with a rod of iron. Moreover, he treads the winepress of the fury of the wrath of God the Almighty. On his outer garment, yes, on his thigh, he has a name written, King of kings and Lord of lords.

Who is the "Lord of lords" and "King of kings"?