is 2 421121 - 1
has 126771 decimal digits
takes 0.004 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-LF681EA3DE3C782C1double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26770.559171.6418 %30000001000000000.11657.1525 %70.675673.6701 %
Target2440.000056.8182 %700011000000.000913.1529 %0.000962.4978 %
Difference+23+70.5591+14.8236 %+2993000+98900000+0.1155-6.0004 %+70.6746+11.1723 %

Known prime factors (1 factor, 70.9 bits, 0.01684011% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
42112122295321751781713890892270.9172647139628726864
24 × 32 × 312709 × 58786009
2009-10-0331270958786009567.420.04920.0841

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2001-11-24ANONYMOUSv4_computers500001000000--0.00119.131%
2001-12-01ANONYMOUSv4_computers500001000000--0.00119.131%
2002-06-15ANONYMOUSv4_computers32768327680012--0.00321.770%
2002-08-24ANONYMOUSv4_computers65536655360012--0.00624.409%
2003-03-27ANONYMOUSv4_computers1310721310720030--0.01226.997%
2016-03-17alpertronManual testing300000010000000012
skipped known factor: 2229532175178171389089
---34.670%


Trial Factoring results:
5758596061626364656667
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2001-03-17ANONYMOUSv4_computers212560.023
2002-01-22ANONYMOUSv4_computers212570.046
2004-01-07ANONYMOUSv4_computers212580.091


ECM factoring results:
Total ECM effort:10.513 GHz-days
Estimated T-Level:26.433
DigitsB1CompleteFacMiss
201100023.8220.000%
25500003.0214.875%
302500000.28775.083%
3510000000.02297.834%
4030000000.00199.860%


ECM Summary

B1B2factorcurvesGHz-days
10.018
5000050000002792.890
250000250000001447.605


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2002-01-02ANONYMOUSv4_computersF681EA3DE3C782C10.004


PRP results:
dateuseridcompidcofactorsres64
2017-09-23Oliver KruseOllaptop
2229532175178171389089
07A1D31E5190C2FD
2017-11-02kkmrkkblmbrbkc4.xlarge
2229532175178171389089
07A1D31E5190C2FD
2020-04-18Oliver KruseAddPrpType5
2229532175178171389089
32C4CE7C8F405F3E


CERT results:
No CERT results for M421121


P-1 factor-bounds graph:
B1 = 3000000, B2 = 100000000 (P-1 stage 2)
B1 = 3000000 (P-1 stage 1)
B1 = 131072, B2 = 13107200 (P-1 stage 2)
B1 = 65536, B2 = 6553600 (P-1 stage 2)
B1 = 32768, B2 = 3276800 (P-1 stage 2)
B1 = 131072 (P-1 stage 1)
B1 = 50000, B2 = 1000000 (P-1 stage 2)
B1 = 65536 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 32768 (P-1 stage 1)
103
104
105
106
107
103
104
105
106
107
108
TF factor-bounds graph:
258
257
256
this exponent TF target: 44
TF double-checked to: 67
ECM T-Level=26.43 ~= 71-bit
250
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Last modified: 2024-02-29T14:28:04+00:00