23,209/Historical Note

Historical Note on $23 \, 209$

The Mersenne number $M_{23 \, 209} = 2^{23 \, 209} - 1$ was demonstrated to be a Mersenne prime on $9$ February $1979$ by Landon Curt Noll, using the same CDC-CYBER-174 that he and Laura Nickel used to discover the primality of $M_{21 \, 701}$.

It took the computer $8$ hours to check the number.

$2$ weeks later, David Slowinski used a CRAY-1 supercomputer to check the result, and it took $7$ minutes.


Sources

  • 1986: David Wells: Curious and Interesting Numbers ... (previous) ... (next): $2^{23209} - 1$
  • 1997: David Wells: Curious and Interesting Numbers (2nd ed.) ... (previous) ... (next): $2^{23,209} - 1$