That’s 20 cm including the hilt. Roughly 15 cm for the blade by itself. And about 1 cm thick. Most likely with no sharp edge to speak of, since it was a toy and I’m sure the dumbass police would have made a point of it if it had.
In other words, ‘wielding’ it in public is about as threatening as carrying a particularly stiff twig. Probably less, considering the size of the hilt.