if the wavelength is -4.09x10^-19J what color would the line be?

4.09 × 10⁻¹⁹ J should be the energy of photon instead.

E = hc/λ, where
Energy of the photon, E = 4.09 × 10⁻¹⁹ J
Planck constant, h = 6.626 × 10⁻³⁴ J s
Speed of light, c = 3.00 × 10⁸ m/s

Wavelength, λ = hc/E = (6.626 × 10⁻³⁴ J s) × (3.00 × 10⁸ m/s) / (4.09 × 10⁻¹⁹ J) = 4.86 × 10⁻⁷ m = 486 nm

Refer to the table below. The color is blue.