is 2 8217973 - 1
has 2473857 decimal digits
takes 2.146 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L2ADB57D3A3FE43B9double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual2673.615765.6716%450007537500.03172.1995%3.647466.4267%0.7551%
PrimeNet2630.194263.4921%360009000000.03153.6210%0.225764.8140%1.3220%
GPU722673.615765.6716%5500013000000.04652.6273%3.662266.5736%0.9019%
Difference----10000-546250-0.0148-0.4278%-0.0148-0.1469%-0.1469%

Known prime factors (1 factor, 63.0 bits, 0.00076681% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
821797393252597297296356971963.016567369820376
23 × 70921227547
2011-08-088709212275470.29641,462.92,732.4

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2002-08-10T00:00:00Team Prime Ribv4_computers45000753750---0.032--2.200%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2011-08-08T06:11:00Carsten KossendeyManual testing??63.016190.1024.3660.208
1998-08-30T00:00:00ANONYMOUSv4_computers21262--0.075--
1999-03-15T00:00:00ANONYMOUSv4_computers21263--0.194--
2011-08-08T06:11:00Carsten KossendeyManual testing263264--0.239--


ECM factoring results:
No ECM results for M8217973


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-11-04T00:00:00Stephen Woodv4_computers2ADB57D3A3FE43B92.146
2003-03-16T00:00:00Team Prime Ribv4_computers2ADB57D3A3FE43B92.146


PRP results:
dateuseridcompidcofactorsres64PRP
2018-09-17T07:30:15Dylan Delgadodesktop
9325259729729635697
435C6598A36045__no
2020-03-16T01:15:27GANKL-SCH09
9325259729729635697
435C6598A3604518no


P-1 factor-bounds graph:
B1 = 45000, B2 = 753750 (P-1 stage 2)
B1 = 45000 (P-1 stage 1)
100
101
102
103
104
105
100
101
102
103
104
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1010
1011
TF factor-bounds graph:
267
264
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262
2
250
260
270
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290
2100
Last modified: 2020-03-16T01:15:27+00:00