"You Know My Name (Look Up the Number)" is a song by the English rock band the Beatles released initially as the B-side of the single "Let It Be" on 6 March 1970.

The song is a music hall comedy number with elements of a Latin style that resembles mambo.

'[4]The lounge section includes a reference to Denis O'Dell, associate producer on the A Hard Day's Night film, whom Lennon had also worked with on How I Won the War.

The reference prompted numerous telephone calls to O'Dell's home by fans who said things such as, "We know your name and now we've got your number.

[11] The recording of the song was left unfinished and untouched until 30 April 1969 when, with the help of Mal Evans, Lennon and McCartney laid down all the vocal tracks and added additional sound effects.

[13] Nick Webb, second engineer on 30 April session, described it this way: John and Paul weren't always getting along that well at this time, but for this song they went out on the studio floor and sang together around one microphone.

[13]Although eventually released as a Beatles song, "You Know My Name (Look Up the Number)" was nearly issued as the A-side of a Plastic Ono Band single.

[14] On 26 November 1969, four months after contributor Brian Jones drowned in his swimming pool,[15] Lennon edited "You Know My Name (Look Up the Number)", reducing the length from 6:08 to 4:19, a more suitable time for a single.

[17] "You Know My Name (Look Up the Number)" was the last Beatles song from the group's official canon to be included on an album, issued on an LP for the first time on Rarities (which had been included as a bonus disc in the British and American boxed set, The Beatles Collection in 1978, and released separately as an album in the United Kingdom in 1979).

[citation needed] The song is a favourite of musician Black Francis, lead singer of Pixies.