654 = 2 x 3 x 109.
654 has a square that is the sum of a cube and fifth power.
The sum 327 + 654 = 981 is one of only four cases in which the equality n + 2n = 3n uses each of the nine digits 1 to 9 once (n = 192, 219, 273, and 327).
654 is 545 in base 11.
654 is a Smith number. The sum of its digits is equal to the sum of the digits of its prime factors: 6 + 5 + 4 = 2 + 3 + 1 + 0 + 9 = 15.
The Auburn Company produced the Auburn 654 automobile in 1936, the year the company went out of business.
