213

213 = 3 x 71.

The sum of the digits of 213 is the same as the product of its digits: 2 + 1 + 3 = 2 x 1 x 3 = 6.

213 is the number of perfect squared rectangles of order 13.

25,986 = 213 x 122 and (backwards) 312 x 221 = 68,952.

213 = 2³ + 2³ + 2³ + 4³ + 5³.

213 was the apartment number of the infamous serial killer Jeffery Dahmer, and the title of a song by the thrash metal band Slayer.

Source: What's Special About This Number?