The song was released as the A-side of Elektra single 45605 in July, 1966. The B-side was "No. Fourteen", supposedly the 'answer' to the half-sentence formed by the A-side's title but actually an out-take from the band's earlier recordings. "7 and 7 Is" made the Billboard Pop Singles chart on July 30, 1966, peaking at number 33 during a ten-week chart run and becoming the band's highest-charting hit single. The recording also featured on the band's second album, Da Capo.
The song drew inspiration from a high school sweetheart of Arthur Lee's, Anita "Pretty" Billings, who shared his birthday, March 7. It also describes Lee's frustration at teenage life - the reference to "in my lonely room I'd sit, my mind in an ice cream cone" being to wearing (in reality or metaphorically) a dunce's cap. Describing how the song came to him, Lee stated: "I was living on Sunset and woke up early one morning. The whole band was asleep. I went in the bathroom, and I wrote those words. My songs used to come to me just before dawn, I would hear them in dreams, but if I didn't get up and write them down, or if I didn't have a tape recorder to hum into, I was through. If I took for granted that I could remember it the next day—boink, it was gone."
It took a great deal of work to record, with Love's drummer, Alban "Snoopy" Pfisterer, being challenged with its frantic demands after 30 takes or so, and being replaced on drums, intermittently, by Arthur Lee himself. It is not clear whether the version eventually released features Pfisterer or Lee, but according to Johnny Echols (lead guitar), in an interview in the book Forever Changes (pg 117) the drumming on the record was Pfisterer. The song climaxes in an apocalyptic explosion - the supposed sound of an atom bomb - before a peaceful conclusion, in a blues form, which then fades out. Although many listeners thought that the explosion at the end of the song was a reverb unit being kicked or dropped, it was (according to the engineer Bruce Botnick in "Forever Changes" book, page 118), in actuality, taken from a sound effects record. He speculated that it was a recording of a gunshot slowed down. (For live performances, the explosion was reproduced by kicking a reverb unit.)
Described as "protopunk", the song was later covered by numerous bands, most notably the Ramones, Alice Cooper, The Electric Prunes, and Rush, as well as a re-recording by Lee himself. The song was used in the film Bottle Rocket, handpicked by director Wes Anderson and music composer Mark Mothersbaugh.