1321
This number is a prime.
π(1321) = 13 * 33 * 23 *
13. [Caldwell]
The smallest emirp that splits up into two consecutive
Fibonacci numbers: 13, 21. Note that the digits consist of
the first four nonzero Fibonacci numbers. [Beedassy]
A prime formed from first Fiboncacci numbers that can be
expressed by first semiprimes raised to first
primes: 4^5+6^3+9^2. [Silva]
For any prime n < 10^11 there is a k such that either
n*2^k + 1 or n*2^k - 1 has all its prime factors greater
than 1321. [Wesolowski]
It requires 1321 gallons of water to make one ream of
paper. [Seametrics]
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