According to independent research, the King James Version (KJV) of the Holy Bible contains 1189 chapters; Psalm 117 is the 595th; there are 594 chapters before Psalm 117, and 594 after it. Thus, it is 117, not 118, that is the center chapter of the Bible.
The KJV has an even number of verses (31,102) and, thus, does not have a single middle verse. The “middle verses” are Psalm 103:1-2, with 15,550 verses before and after.
Psalms 103: 1-2: A Psalm of David. Bless the LORD, O my soul: and all that is within me, bless his holy name. Bless the LORD, O my soul, and forget not all his benefits:
There are small variations in the number of verses from one Bible version to another. The order of the books in the Bible was not settled until the 4th century, the Hebrew Old Testament puts the books in a different order than that used by Christians, and the division into chapters and verses was done between the 13th and 16th centuries.
Since the Bible wasn’t divided into chapters and verses until hundreds of years after its completion, and since not all Bibles have the books in the same order, this is a pointless discussion.