216 (number)

← 215 217 → 216
← 200 210 220 230 240 250 260 270 280 290 → List of numbers — Integers ← 0 100 200 300 400 500 600 700 800 900 →
Cardinal	two hundred [and] sixteen
Ordinal	216th (two hundred [and] sixteenth)
Factorization	$2^3 \cdot 3^3$
Divisors	1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 27, 36, 54, 72, 108, 216
Roman numeral	CCXVI
Binary	110110002
Octal	3308
Duodecimal	16012
Hexadecimal	D816

216 is the natural number following 215 and preceding 217.

Since $216 = 3^3 + 4^3 + 5^3 = 6^3$, it is the smallest cube that's also the sum of three cubes (Plato was among the first to notice this, and mentioned it in Book VIII of Republic). It is also the sum of a twin prime (107 + 109). But since there is no way to express it as the sum of the proper divisors of any other integer, it is an untouchable number.

This multiplicative magic square

$\begin{pmatrix} 2 & 9 & 12\\ 36 & 6 & 1\\ 3 & 4 & 18 \end{pmatrix}$

has magic constant 216.

In base 10, it is a Harshad number.

There are 216 fixed hexominoes, the polyominoes made from 6 squares.

216 is a Friedman number

In other fields

• The 216 colors formed by a 6×6×6 color cube are sometimes known as the web-safe color palette.
• ISO 216 is the ISO's standard for paper sizes.
• In the film Pi, Max becomes obsessed with a 216-digit number in his quest to find the numeric equation behind existence, and is told by a group of Hasidic Jews that it represents the true name of God.
• As six cubed (6*6*6), 216 is also symbolic of the Mark of the Beast in Christianity. This has been expressed in the Left Behind series.
• According to the Ken Burns series Baseball, it is the number of stitches on a baseball.

See also

• The year 216

References

• Wells, D. (1987). The Penguin Dictionary of Curious and Interesting Numbers (p. 144). London: Penguin Group.