is 2 908321 - 1
has 273432 decimal digits
takes 0.022 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-LBB7BE86D47F7F1B9double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26732.713070.1493 %1055000295400000.09175.7392 %32.804771.8625 %
Target2440.000054.5455 %1500030000000.006218.0046 %0.006262.7294 %
Difference+23+32.7130+15.6038 %+1040000+26540000+0.0854-12.2654 %+32.7984+9.1331 %

Known prime factors (1 factor, 75.4 bits, 0.00830337% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
908321505887585161716217945832375.42127847401147926571
3 × 31 × 137 × 347 × 6298710973
2014-02-0334762987109738,424.212.06722.537

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2002-01-08ANONYMOUSv4_computers2000200000--0.00012.159%
2002-02-17ANONYMOUSv4_computers4096409600--0.00115.082%
2002-04-28ANONYMOUSv4_computers8192819200--0.00217.880%
2002-05-18ANONYMOUSv4_computers163841638400--0.00420.640%
2002-07-14ANONYMOUSv4_computers32768327680012--0.00723.356%
2002-12-25ANONYMOUSv4_computers65536655360012--0.01526.020%
2003-07-30ANONYMOUSv4_computers1310721310720012--0.02928.626%
2011-06-07JossManual testing200000200000--0.00715.553%
2011-07-13JossManual testing225802225802--0.00815.931%
2011-09-11JossManual testing376336376336--0.01317.522%
2011-12-10JossManual testing752673752673--0.02619.677%
2012-06-19JossManual testing908489908489--0.03220.259%
2013-10-08David Campeaui5-2500k10550002954000012--0.09232.278%
2016-03-17alpertronManual testing20000050000006---26.210%


Trial Factoring results:
5758596061626364656667
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2000-12-14ANONYMOUSv4_computers212560.011
2001-10-06ANONYMOUSv4_computers212570.021
2003-03-16ANONYMOUSv4_computers212580.042
2022-03-07LordJuliusManual testing258260
2010-05-31Architects Cubedm1_f22602610.169


ECM factoring results:
Total ECM effort:13.960 GHz-days
Estimated T-Level:25.654
DigitsB1CompleteFacMiss
201100014.6920.000%
25500001.60920.008%
302500000.13187.737%
3510000000.00999.133%


ECM Summary

B1B2factorcurvesGHz-days
10.084
5000050000002787.690
25000025000000446.186


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2001-12-22ANONYMOUSv4_computersBB7BE86D47F7F1B90.022


PRP results:
dateuseridcompidcofactorsres64
2017-09-28Oliver KruseGTX-2
50588758516171621794583
5B34D2AC8471A01C
2017-10-14Oliver KruseThreadripper-PC
50588758516171621794583
5B34D2AC8471A01C
2017-12-20ATHec2-1xh
50588758516171621794583
5B34D2AC8471A01C
2020-04-23Oliver KruseAddPrpType5
50588758516171621794583
F2FB91F005A5F959


CERT results:
No CERT results for M908321


P-1 factor-bounds graph:
B1 = 1055000, B2 = 29540000 (P-1 stage 2)
B1 = 1055000 (P-1 stage 1)
B1 = 908489 (P-1 stage 1)
B1 = 131072, B2 = 13107200 (P-1 stage 2)
B1 = 752673 (P-1 stage 1)
B1 = 200000, B2 = 5000000 (P-1 stage 2)
B1 = 65536, B2 = 6553600 (P-1 stage 2)
B1 = 376336 (P-1 stage 1)
B1 = 225802 (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 = 65536 (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)
101
102
103
104
105
106
107
101
102
103
104
105
106
107
108
109
1010
TF factor-bounds graph:
261
260
258
257
256
this exponent TF target: 44
TF double-checked to: 67
ECM T-Level=25.65 ~= 69-bit
250
260
270
280
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Last modified: 2024-03-03T02:29:32+00:00