The iOS itself is not factored into Others. The iOS partition is already taken out when you see your max capacity in Settings or iTunes. Others usually consists of cache, fragmented downloads for apps that have sandboxed downloading like Mercury browser, image caches, messages caches, some app data, cookies, history, and the list goes on.
So for iOS 7.0.6, for the non-iPhone 5S small form factor devices, you should get around 13.30-13.37 available memory if you're on a 16GB device. iOS will round upwards for flexibility purposes, so 16-13.37 = 2.63, of which, you'd lose about 300-500 from storage conversion (KB to MB is 1024:1 rather than 1000:1). So that gives you about 2.1 GB. The iOS itself only takes up 1.5 or so, leaving 600 as leverage space