Behold, the Lord’s hand is not shortened, that it cannot save, or his ear dull, that it cannot hear; but your iniquities have made a separation between you and your God, and your sins have hidden his face from you so that he does not hear. (Isaiah 59:1)

The eyes of the LORD are upon the righteous, and his ears are open unto their cry. The face of the LORD is against them that do evil, to cut off the remembrance of them from the earth.” (Psalm 34:15-16)

If I regard iniquity in my heart, the Lord will not hear me: (Psalm 66:18)
The LORD is far from the wicked: but he heareth the prayer of the righteous. (Proverbs 15:29)

Behold, the LORD’S hand is not shortened, that it cannot save; neither his ear heavy, that it cannot hear: But your iniquities have separated between you and your God, and your sins have hid his face from you, that he will not hear. (Isaiah 59:1-2)

For the eyes of the Lord are over the righteous, and his ears are open unto their prayers: but the face of the Lord is against them that do evil. (1 Peter 3:12)

And whatever we ask we receive from Him, because we keep His commandments and do those things that are pleasing in His sight. (1 John 3:22)

Now we know that God does not hear sinners; but if anyone is a worshiper of God and does His will, He hears him. (John 9:31)

One who turns away his ear from hearing the law, even his prayer is an abomination. (Proverbs 28:9)

I believe the answer to the question is plainly stated in these passages. God does not hear (respond to) the prayer of the wicked (unbeliever).