Library E. W. Bullinger Number in Scripture
Part II — Spiritual Significance
Sixty-five
being a multiple of thirteen (13x5=65), is specially associated with Ephraim (see Isa 7:8), and marks the apostasy of that Tribe. This apostasy, which began in Judg 17, afterwards extended to the Ten-Tribe kingdom, which is frequently spoken of therefore under the name of "Ephraim."
"Within three-score and five years shall Ephraim be broken that it be not a people."
E. W. Bullinger, Number in Scripture: Its Supernatural Design and Spiritual Significance, fourth edition revised (London: Eyre & Spottiswoode, 1921). Public domain. Sectioned HTML transcription via Levend Water; bibliographic record and page scan of the 1894 edition from the Claremont School of Theology collection via Internet Archive.