The first foreigner to become a samurai was an African slave.
26
The 1 yen coin can be used as a weight, because it weighs exactly one gram. Also, it can float on water.
19
The Japanese, on average, are the shortest people.
320
In Japan, more adult diapers are sold than baby diapers.
50
In Japan, it is tradition for husbands to get a monthly allowance from their wives.
6