245
This number is a composite.
The number 245*2^9+1 is a Proth prime. [Patterson]
245, 246, and 247 are the smallest three consecutive
composite numbers whose concatenations of prime factors in
ascending order (577, 2341, and 1319) are prime numbers. [Gaydos]
The expression 1*3*5*7*11*13*15*...*243*245 +/-2 produces
the third and largest known pair (241-digits each) of "cousin" primes (that
differ by 4) of this type. [Rivera]
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