Fifty-seven is the sixteenth discrete semiprime and the sixth in the (3.q) family. With 58 it forms the fourth discrete bi-prime pair. 57 has an aliquot sum of 23 and is the first composite member of the 23-aliquot tree. Although 57 is not prime, it is jokingly known as the "Grothendieck prime" after a story in which Grothendieck supposedly gave it as an example of a particular prime number. This story is repeated in Part 2 of a biographical article on Grothendieck in Notices of the American Mathematical Society.
In the first storyboard draft for Pixar's film Cars, the main character, a race car named Lightning McQueen was going to have number 57 as his racing number, in reference to director John Lasseter's birthdate, January 12, 1957. But in the final cut, Lightning's racing number changed to 95.
Rudyard Kipling in The Man Who Would be King, short story, has his character Peachy state: "This business is our Fifty-Seven" after he and Daniel are discovered to be men, not gods. This alludes to the Indian Rebellion in 1857, or India's First War of Independence, against British Rule
Heinz 57, a brand of sauce, and the number of varieties of foods claimed to be produced by the H.J. Heinz Company
"Prop(osition) 57", one of a number of anti-ketchup packet groups on Facebook designed to bring attention to the shortcomings of take-out condiment packaging; its name is a reference to Heinz Co., which debuted a new design in test markets in early 2010