Welcome to the forum.
My DD was a number and letter loving toddler too. We also speak multiple languages and she didn't start speaking until she turned 2 and by then, she could read. It took me awhile to figure out what to do with a child who defied everything I knew about cognitive development.
When I talked to a friend/coworker who has raised two gifted children, she told me one thing she regrets is that she didn't do more to help them develop social skills when they were younger. My DD back then didn't have social issues but as she got a little older, slowly but surely, things became problematic and I would see that she needed support in some areas like relating to age-peers, overcoming perfectionism, and dealing with a sense of isolation. We found a tiny little school that didn't mind that she is intense, high-maintenance, and academically advanced for her age. Her problems haven't gone away completely and we have our ups and downs but the teacher is willing to work with us and with DD.
I also recommend finding an activity that your DS would enjoy even if it's not exactly his forte. For DD, it was ballet. She was so horrible at it but it didn't matter because she loved it and had fun. I think that kind of freedom with learning process is a good thing to develop.
If I could undo anything I did is pushing her to discover popular culture so she has something in common with girls her age. I think we've gone a bit too far with this and now, I have a child who is completely addicted to My Little Ponies. I suppose there are worse things than MLP (i.e., Frozen) but OMG, I can't get the sound of Pinkie Pie's voice out of my head.