1451
This number is a prime.
The roof of Chicago's Willis Tower is 1451 feet above ground level.
The other eleven permutations of the digits of 1451 are all
semiprimes. [Gaydos]
1451 is the lesser member of a twin prime pair: (1451,1453). Curiously, if we take the sum of digits of
both numbers, we also get a twin prime pair. [Anitha]
(There is one curio for this number that has not yet been approved by an editor.)
Printed from the PrimePages <t5k.org> © G. L. Honaker and Chris K. Caldwell