English has an expression, baker's dozen. It means 13, just like the "devil's dozen" in Russian. The expression devil's dozen exists in English too — and the patent dispute over whose dozen it really is, the devils' or the bakers', isn't over yet.
But what's the story here? Were English bakers really so fierce that they wanted to take the dozen away from the devils themselves? It turns out it's the other way around.
The thing is, in medieval England there was a popular pastime: beating up bakers. Prices for baked goods were tied by law to the cost of the raw material that went into them, that is, flour. And for short-weighting their goods, bakers were not only heavily fined but could also get a good thrashing.
Everyone loved this, except, for some reason, the bakers. The situation was made worse by the fact that few of them had accurate enough scales. So when someone ordered a dozen, that is 12 loaves, the baker simply threw in a thirteenth for free. That way he saved the order from possibly being underweight, and his buns from a beating.
The law regulating the price, weight and quality of bread (and also beer) was called, by the way, the Assize of Bread and Ale. The name itself seemed to hint at exactly what bakers should be protecting.
They say that bakers who were especially intolerant of pain handed over all fourteen loaves. But apparently they went broke quickly. So the expression baker's dozen, still used today, does mean 13 after all.