I refer to the letter Who created the creator then? by SK Wong.
According to the law of mathematics, if you keep dividing any number, you will go on for eternity until you divide the number by the same number in which case, you will get the number one.
Also, if you keep adding the digits in any number you will always end up with the number one. Which is why the Quran states: "Say, that God is one". In mathematics, the number one is the smallest prime number, and the ultimate square root of all numbers is always the number one.
All religions believe in one God, just the name differs. Albert Einstein's equation states that Energy = Mass x C 2 . The law of physics states that energy cannot be created or destroyed.
Which means the energy that created the universe cannot have a beginning nor an end. Also, there must be something that existed before the universe and that will continue to exist after the universe. That is the definition of God.
By applying Albert Einstein's formula, the universe must have a creator because the universe has mass (M). God does not need a creator because God does not have mass (M). God is energy (E).
Thus when people ask the question, "If God created mankind, who created God?", they mistakenly imagine God as having a form or mass. Only mass needs a creator, not energy.
The creator of mass is of course, energy. The theory of God's existence is in line with mathematical theory.