For the year A.D. 54, see 54.
Fifty-four (54, LIV) is the natural number following fifty-three and preceeding fifty-five. Its divisors are 1, 2, 3, 6, 9, 18, 27, and 54; its factorisation is
- The atomic number of xenon.
- The degree part of the coordinate 54° 40', used in the slogan "54° 40' or Fight!" for the presidential campaign of James K. Polk.
- The code for international direct dial phone calls to Argentina.
- The title of a 1998 movie starring Salma Hayek and Ryan Phillippe.
- The number of colored squares on a Rubik's cube.