Gasoline Alley by Jim Scancarelli for September 17, 2019

There is a police detective character by a very popular author who has this condition and may have been the source. See David Baldacci. I believe the guy has been the subject of his latest and a previous story.

Tori Amos has “chromesthesia” and sees music as colors, which would be a subset of this condition https://en.wikipedia.org/wiki/Tori_Amos

Ssid forms of synestesia are slightly different than being an “empath”.

Be it sight, sound, smell, or touch,

There’s something inside, that we need so much.

The sight of a touch, or the scent of a sound,

Or the strength of an oak, with roots, deep in the ground.

The wonder of flowers, to be covered, and then to burst up,

Through tarmac, to the sun again, or to fly to the sun,

Without burning a wing, to lie in a meadow,

And hear the grass sing. To have all these things,

In our memories hoard, and to use them,

To help us, to find the lost chord… (Moody Blues)

Some people visualize numbers in odd geometric shapes; see “number form” (note: not “forms”) in Wikipedia. And Alfred Bester’s famous science-fiction novel, “The Stars My Destination” (also known as “Tiger! Tiger!”) has a legendary feast of synesthesia near the end, as the protagonist experiences an explosion of psychic powers that he is not prepared for.