Probably, currently in the magna, anything from 20+. Kakashi can do about what 6-7 Lightening Blades with his normal-ish chakra, so Naruto with his super Uzumaki chakra can do double that plus more.
We should count how many type of rasengan he used against Kyuubi... I remember that he combined several rasengans of kagebunshins and made one that is bigger than Kyuubi itself..