is 2 3147721 - 1
has 947559 decimal digits
takes 0.268 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L25963A2B86FBA42Adouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26937.928068.1159%31477216686618404.86329.7228%42.791271.2160%3.1000%
PrimeNet2600.048863.3333%130002400000.00312.6495%0.051964.3048%0.9715%
GPU722641.130865.6250%150002400000.00341.5440%1.134166.1558%0.5308%
Difference+5+36.7972+2.4909%+3132721+668421840+4.8599+8.1788%+41.6571+5.0602%+5.0602%

Known prime factors (1 factor, 89.6 bits, 0.00284744% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
31477219576183340987496697001733772789.630152112962695669290528
25 × 3 × 32203 × 637573 × 77173597
2019-04-066375737717359751,623,0120.59330.9692

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2004-02-07T00:00:00ANONYMOUSv4_computers2048204800---0.002--0.202%
2009-07-03T07:24:00Carsten Kossendeyleela15000183750---0.003--0.657%
2011-09-06T18:30:00Squeeky_SquirrelT7500_220055000935000---0.013--1.600%
2013-09-02T09:04:00Squeeky_SquirrelP4_26001100002475000---0.029--2.387%
2016-11-15T10:24:24Squeeky_SquirrelP4_2600195000546000012---0.059--3.166%
2018-07-12T10:20:23Jocelyn Larouchelow 4M636000636000012---0.117--3.836%
2019-04-06T03:20:20mikrMSI3000000100000000122789.6301.0220.5362.0457.430%
2021-11-20T20:53:50Jocelyn LaroucheManual testing31477213147721---0.388--3.426%
2021-12-09T14:58:54Jocelyn LaroucheManual testing31477213147721012---0.579--6.092%
2021-12-21T19:29:56Jocelyn LaroucheManual testing3147721140228550-
skipped known factor: 957618334098749669700173377
--1.310--7.859%
2021-12-22T09:19:53Jocelyn LaroucheManual testing3147721668661840-
skipped known factor: 957618334098749669700173377
--4.863--9.723%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2001-05-27T00:00:00ANONYMOUSv4_computers21260--0.049--
2009-04-12T05:17:00S485122USB-Z260261--0.049--
2011-11-04T02:10:00markroldgamer261262--0.098--
2013-01-07T14:05:00dbaughManual testing262263--0.312--
2015-02-11T09:10:00VictordeHollanderManual testing263264--0.624--
2015-02-11T09:10:00VictordeHollanderManual testing264265--1.187--
2015-06-17T09:59:00ThaManual testing265266--2.374--
2021-01-03T13:46:16Jocelyn LaroucheManual testing265266--2.374--
2017-04-20T01:22:37Gordon SpenceManual testing266267--4.748--
2018-12-24T09:14:09TJAOIManual testing267268--9.496--
2022-01-09T02:58:42Jocelyn LaroucheManual testing268269--18.99--


ECM factoring results:

Old Calculation Method

Total ECM effort:1.757 GHz-days
Estimated T-Level:0.750
DigitsB1CurvesCompleteFacMiss
201100015 / 1000.15086.006%
255000015 / 2800.05494.775%

New Calculation Method

Total ECM effort:1.757 GHz-days
Estimated T-Level:0.750
DigitsB1CompleteFacMiss
20110000.48461.639%
25500000.04495.721%
302500000.00399.731%


ECM Summary

B1B2factorcurvesGHz-days
500005000000151.757


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-05-30T00:00:00ANONYMOUSv4_computers25963A2B86FBA42A0.268


PRP results:
dateuseridcompidcofactorsres64PRP
2019-04-06T04:38:39ATHec2-PRPCF
957618334098749669700173377
98C8649EE7D335ADno
2019-04-07T00:36:27oodairacom1
957618334098749669700173377
98C8649EE7D335ADno


P-1 factor-bounds graph:
B1 = 3147721, B2 = 668661840 (P-1 stage 2)
B1 = 3147721, B2 = 140228550 (P-1 stage 2)
B1 = 3000000, B2 = 100000000 (P-1 stage 2)
B1 = 3147721, B2 = 31477210 (P-1 stage 2)
B1 = 3147721 (P-1 stage 1)
B1 = 3000000 (P-1 stage 1)
B1 = 636000, B2 = 6360000 (P-1 stage 2)
B1 = 636000 (P-1 stage 1)
B1 = 195000, B2 = 5460000 (P-1 stage 2)
B1 = 110000, B2 = 2475000 (P-1 stage 2)
B1 = 195000 (P-1 stage 1)
B1 = 110000 (P-1 stage 1)
B1 = 55000, B2 = 935000 (P-1 stage 2)
B1 = 55000 (P-1 stage 1)
B1 = 15000, B2 = 183750 (P-1 stage 2)
B1 = 15000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
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TF factor-bounds graph:
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Last modified: 2022-01-09T02:58:42+00:00