I took a photo of the sign that I uploaded here: https://files.catbox.moe/crtvnp.jpg and you can also see the sign on Google Maps street view here: https://maps.app.goo.gl/HSxidkzG4TirnKTs7?g_st=ac I'm still very new to this stuff so let me know if I am misinterpreting the meaning of the sign but I think the road really is named 3451.

The street sign just said "3451" I thought it was odd as well when I saw it. I'll go double check tomorrow just in case.