It looks like a hoya of some sort. If it is then it's a succulent. You can usually tell by the leaves.

Oh, I see it now, rina. The flower is a bit like my ceropegia woodii in the way it's attached.

Definitely a Ceropegia, you can tell by the flower, so yes, a succulent.

Yes Marguerite, it looked like hoya to me at first too, but the flower is so different. I don't have any, but looked them up when I saw photos posted on another forum. I like those unusual flowers a lot.
Rina

Interesting plant. The flowers are so unusual.