The results show had a record 14.8million viewers, eclipsing the previous best of 14.6million for last year's final.
Girls Aloud star Cheryl, 26, sang her solo single Fight For This Love and Whitney Houston, 46, also made her long-awaited comeback.
The Saturday show also proved popular with 12.2million people tuning in.
It meant The X Factor easily beat Strictly Come Dancing, which had 8.5million viewers.
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