He ghosted me and text me a month later what does this mean ?

he probably had a girl lined up but he realized that girl isn't interested, or maybe she is interested but sucked in bed, not sure, so he said to himself man I rather have my old girl so hence the text. 

He may just be inconsiderate. He may have found someone else who didn't work out. Or he may just want to lead you to think that maybe there's something wrong with you and you should be thankful he showed back up. If you have even a hint that it's the latter, avoid him completely.

Why didn't you ask what it meant?

It means they have low priorities. Block, ignore and move on.

the girl he ghosted you for isn't interested in him and he's desperate and trying it with you again because he's bored and overall a terrible person

Theres a ghost in your house? Oh no. Wait. I think theres a ghost in my house too AHHH what are you doing let go of me thats my phone dont take my phone away AHHH!!!!! HOOO HOOO HOOOO HOOO HOO HOOO HOOO HOOO IM THE GHOST WHO TOOK NAYA’S PHONE HOO HOOO HOO HOOOO

That depends on why he ghosted you and what he wanted when he got back in touch with you.

It means he wants to remain on good terms with you.