208

Number

$208$ (two hundred and eight) is:

$2^4 \times 13$

The $5$th after $4$, $13$, $38$, $87$ in the sequence formed by adding the squares of the first $n$ primes:

$208 = \ds \sum_{i \mathop = 1}^5 {p_i}^2 = 2^2 + 3^2 + 5^2 + 7^2 + 11^2$

The $6$th positive integer after $200$, $202$, $204$, $205$, $206$ that cannot be made into a prime number by changing just $1$ digit

The $34$th happy number after $1$, $7$, $10$, $13$, $19$, $23$, $\ldots$, $130$, $133$, $139$, $167$, $176$, $188$, $190$, $192$, $193$, $203$:

$208 \to 2^2 + 0^2 + 8^2 = 4 + 0 + 64 = 68 \to 6^2 + 8^2 = 36 + 64 = 100 \to 1^2 + 0^2 + 0^2 = 1$