To factor the quadratic equation \( x^2 + 10x + 16 = 0 \), we look for two numbers that multiply to \( 16 \) (the constant term) and add up to \( 10 \) (the coefficient of the linear term).
The numbers that satisfy these conditions are \( 2 \) and \( 8 \), since:
- \( 2 \times 8 = 16 \)
- \( 2 + 8 = 10 \)
Thus, the factored form of the equation is:
\[ (x + 2)(x + 8) = 0 \]
So the numbers to write it in factored form are 2 and 8, with the lesser number first.