279

279 = 3² x 31.

279 can be expressed as a prime raised to three consecutive primes: 279 = 3² + 3³ + 3⁵.

279 = (27 x 9) + (27 + 9).

279 is the maximum number of 8th powers needed to sum to any number.

279 is a number that cannot be written as a sum of three squares.

The longer side of a standard "letter-size" sheet of paper in the United States is 11 inches or about 279 millimeters.

Source: Prime Curios!