I'm no expert, but I'm surprised no one has asked if there are holes in that pot so it can drain. They'll also ask about your soil, cacti and succulents don't do well in regular potting soil. That's about the extent of my expertise, but others here can help you :)

Its a pilosocereus, with a few species in mind.

that's crazy! I have the slightest feeling it may be epiphyllum because I have a vague memory or the parent being a draped plant but I coincidentally did a post before this (not sure if you can find it thru my name) and it turns out I have another upstairs. the this plant is just so thick I can't imagine in hanging. what can I do to accelerate its growth? or is it just such a slow growing plant? I do recall the other upstairs taking years to do much and all the sudden it just took off and won't stop growing!

You have the exact same one I have. Have not been able to properly id for the last 3 or 4 years. Here are a few names it could be. They all look very identical... These needles get quite long as it ages. Very easy to flower indoors I have found and they seem to pup around the base. Mammillaria ingens Mammillaria durispina (llifle.com) Mammillaria kewensis (llifle.com)