what kind of a buffer is this?

I’m using a weird blockchain and it’s API returns data like this:

0x36333562663261376537333436376636333363313931353738613938383137313663383633306235373164613034643634303334356331646232333231636537

Now, i know this is a string I sent in that was actually 64 hex as a string
And I get back 128 chars (plus 0x) as the above.

So can anyone suggest how to decode this?
since its all numbers, i’m assuming it’s something base10, but then we would have different byte lengths (64 vs 128) etc.

Since there are lots of 2s and 3s i was guessing maybe that is an indicator for a byte of 2 vs 3

Is it a unicode array of some type?
The ‘0x’ at the front makes me think it’s hex values but there’s no actual DEADBEEF here…

now I know the original string i passed in was 64 hex characters.
I’m getting back 128 decimals.

I’m looking for a converter in JS to get back the hex ‘string’

I’ve tried atob and Buffer but haven’t cracked it yet…

Javascript – Converting between Unicode string and ArrayBuffer