M43 is the short hand used to refer to the 43rd Mersenne prime 230,402,457-1.
The number is 9,152,052 decimal digits long.
This prime number was the ninth record prime found by the GIMPS project.
The new prime was independently verified:
- by Tony Reix of Bull S.A. in Grenoble, France, in 5 days using 16 Itanium2 1.5 GHz CPUs of a Bull NovaScale 6160 HPC at Bull Grenoble Research Center, running the Glucas program;
- by Jeff Gilchrist of Elytra Enterprises Inc. in Ottawa, Canada, in 14 days using 14 CPUs of a Compaq Alpha GS160 1.2 GHz CPU server at SHARCNET.
- GIMPS Discovers 43rd Mersenne Prime (press release)