Who knows forty-seven?
Please cite/link your sources, if possible. At some point in the next few days, I will:
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47 are the prohibitory mitzvos in the Torah portion of Ki Teitzei (according to the Chinuch's listing) - the most in any one portion.
47 are also the positive mitzvos in the Rambam's Sefer Ha'Avodah (dealing with the laws of the Temple) - again, the most in any one book of his Mishneh Torah.
Automatic Kalishnikov rifle, model 1947, also known as AK-47
Arguably responsible for more Jewish deaths than any weapon since WWII.
I know, that is a pretty depressing answer. I encourage everyone to down-vote it!