First of all, God is not a man. Second, I would submit to you that if God was taking the test and answered saying, "All worms have nine hearts"; then you would have trouble finding a worm in existence with more or less than exactly nine hearts. You see, God is God. I have scripture that supports this.....
Genesis 1:3 And God said, "Let there be light," and there was light.
God's words have authority and power. Scripture is some of His words, but not all. Did God lie to us because some of His words remain unwritten?
2 Kings 20:1 In those days Hezekiah was sick and near death. And Isaiah the prophet, the son of Amoz, went to him and said to him, “Thus says the LORD: ‘Set your house in order, for you shall die, and not live.’”
Is Hezekiah dead?
It's a non-issue. Atheist's have argued with Christians about this forever. I think that you would be wise to accept the words of the other figures in the Bible who've supported this number. I haven't, nor will I do the math.
Maybe you could start with this one....
John 17:12 'While I was with them, I protected them and kept them safe by that name you gave me. None has been lost except the one doomed to destruction' so that Scripture would be fulfilled.
Was Jesus lying when He said the Scripture would be fulfilled?
Was Jesus lying when He said Judas was doomed to destruction?
If not, how did Jesus know future free will acts?