7

This number is a prime.

Just showing those entries submitted by 'Olry': (Click here to show all)

The last digit of Graham's number, and the rarest digit among the 500 rightmost decimal digits of Graham's number (these 500 digits include 56 0s, 56 2s, 56 9s, 55 5s, 54 8s, 49 1s, 47 3s, 46 4s, 46 6s, but only 35 7s). [Olry]

The notorius Khmer Rouge jail Monti Santésok, also referred to as S-21, contained between 14,000 and 16,000 prisoners. Only 7 of them could survive. Ref: Panh R. (2003) La machine Khmère Rouge. Paris, Flammarion, p. 34. [Olry]