is 2 867211 - 1
has 261057 decimal digits
takes 0.021 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L51DA5E86DEB4212Bdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26868.731770.5882 %35000000999230003772019,143.912424.0453 %19,212.644177.6604 %
Target2440.000054.5455 %1400027500000.005717.6075 %0.005762.5489 %
Difference+24+68.7317+16.0428 %+34986000+9992297287720+19,143.9067+6.4378%+19,212.6384+15.1115 %

Known prime factors:
No known factors for M867211

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2002-01-08ANONYMOUSv4_computers2000200000--0.00012.073%
2002-02-17ANONYMOUSv4_computers4096409600--0.00114.992%
2002-04-14ANONYMOUSv4_computers8192819200--0.00217.787%
2002-05-25ANONYMOUSv4_computers163841638400--0.00420.545%
2002-06-29ANONYMOUSv4_computers32768327680012--0.00723.259%
2002-12-16ANONYMOUSv4_computers65537655370012--0.01525.922%
2003-08-25ANONYMOUSv4_computers1310721310720012--0.02928.526%
2011-02-20JossManual testing200000200000--0.00715.479%
2011-07-12JossManual testing239777239777--0.00816.043%
2011-08-31JossManual testing399629399629--0.01417.632%
2012-01-22JossManual testing799258799258--0.02819.784%
2012-03-29JossManual testing11988881198888--0.04221.036%
2012-09-21JossManual testing17344221734422--0.06122.169%
2012-10-25JossManual testing19439511943951--0.06822.518%
2013-11-09David Campeaui5-2500k20200007272000012--0.20635.108%
2015-12-01Sid & AndyRocky867211026016330012--0.78739.155%
2022-08-26lycorncolab_DG_1150000001101081888270--2,22760.785%
2024-03-10Ethan O'ConnorVirginia350000009992300037720--19,14466.009%


P+1 Factoring results:
dateuseridcompidb1b2startfactorSmoothdigitsbits*ghz-days
2023-03-16masserManual testing600000028800000027--0.850
2023-03-16masserManual testing600000027600000012317--0.828
2023-03-30masserManual testing600000028200000065--0.839


Trial Factoring results:
575859606162636465666768
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2000-08-24ANONYMOUSv4_computers212550.006
2000-12-31ANONYMOUSv4_computers212560.011
2001-12-01ANONYMOUSv4_computers212570.022
2003-09-09ANONYMOUSv4_computers212580.044
2022-03-07LordJuliusManual testing258259
2004-05-11Sturle Sundev4_computers212600.089
2010-05-20Architects Cubeda3_bu22602610.177
2015-02-06TJAOIManual testing2612620.354
2015-10-11Gordon SpenceManual testing2622643.396
2016-02-12lycornManual testing2642654.308
2018-05-18BloodERazorManual testing2652668.617
2019-03-21lycornManual testing26626717.23
2022-02-23Gordon SpenceManual testing26726834.47


ECM factoring results:
Total ECM effort:14.702 GHz-days
Estimated T-Level:25.703
DigitsB1CompleteFacMiss
201100015.3150.000%
25500001.70118.256%
302500000.14186.883%
3510000000.01099.052%


ECM Summary

B1B2factorcurvesGHz-days
5000050000002807.709
25000025000000506.993


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2002-01-28ANONYMOUSv4_computers51DA5E86DEB4212B0.021
2015-04-11MadPooManual testing51DA5E86DEB4212B0.021


PRP results:
No PRP results for M867211


CERT results:
No CERT results for M867211


P-1 factor-bounds graph:
B1 = 35000000, B2 = 9992300037720 (P-1 stage 2)
B1 = 15000000, B2 = 1101081888270 (P-1 stage 2)
B1 = 35000000 (P-1 stage 1)
B1 = 8672110, B2 = 260163300 (P-1 stage 2)
B1 = 15000000 (P-1 stage 1)
B1 = 8672110 (P-1 stage 1)
B1 = 2020000, B2 = 72720000 (P-1 stage 2)
B1 = 2020000 (P-1 stage 1)
B1 = 1943951 (P-1 stage 1)
B1 = 1734422 (P-1 stage 1)
B1 = 1198888 (P-1 stage 1)
B1 = 131072, B2 = 13107200 (P-1 stage 2)
B1 = 799258 (P-1 stage 1)
B1 = 65537, B2 = 6553700 (P-1 stage 2)
B1 = 399629 (P-1 stage 1)
B1 = 239777 (P-1 stage 1)
B1 = 32768, B2 = 3276800 (P-1 stage 2)
B1 = 200000 (P-1 stage 1)
B1 = 131072 (P-1 stage 1)
B1 = 16384, B2 = 1638400 (P-1 stage 2)
B1 = 65537 (P-1 stage 1)
B1 = 8192, B2 = 819200 (P-1 stage 2)
B1 = 32768 (P-1 stage 1)
B1 = 4096, B2 = 409600 (P-1 stage 2)
B1 = 16384 (P-1 stage 1)
B1 = 2000, B2 = 200000 (P-1 stage 2)
B1 = 8192 (P-1 stage 1)
B1 = 4096 (P-1 stage 1)
B1 = 2000 (P-1 stage 1)
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TF factor-bounds graph:
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this exponent TF target: 44
TF double-checked to: 67
ECM T-Level=25.7 ~= 69-bit
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Last modified: 2024-03-13T02:15:48+00:00