What color has a wavelength of 6.49*10^23?

Wavelength of any wave can't be equal to the number with exponential of 23, otherwise, if you're focusing on visible light, and neglecting the exponential then your color would be: orange. [ Again, remember wavelengths can be in between 10 to 10^-14 ]

In short, Your Answer would be: Orange

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The color would be orange. If you have any other questions like this just look at the wavelength spectrum.

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