is 2 2027401 - 1
has 610309 decimal digits
takes 0.133 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L6C2FC3E321FB7BC7double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26829.399669.1176%40000002000000001.39948.7517%30.799171.8204%2.7027%
PrimeNet2580.018963.7931%90001500000.00162.6138%0.020564.7395%0.9464%
GPU722620.303066.1290%80001200000.00131.2743%0.304466.5606%0.4316%
Difference+6+29.0966+2.9886%+3992000+199880000+1.3981+7.4774%+30.4947+5.2597%+5.2597%

Known prime factors (1 factor, 76.9 bits, 0.00379405% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
20274011430252601714805139872872476.92135273056531855443
3 × 7 × 4597 × 365383806539
2020-03-27459736538380653913,8281,897.93,544.7

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-02-24T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.221%
2007-07-04T00:00:00markrv4_computers2000003500000---0.036--3.026%
2010-12-14T09:47:00Jocelyn LaroucheManual testing202740202740---0.019--1.172%
2013-10-18T21:26:00David Campeaui5-2500k58000015080000---0.131--4.747%
2019-04-06T02:45:32mikrMSI400000020000000012---1.399--8.752%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-01-02T00:00:00ANONYMOUSv4_computers21258--0.019--
2016-02-23T16:29:03Mark RoseManual testing258260--0.057--
2009-01-02T23:45:00Sturle Sundegehry.ifi260261--0.076--
2010-02-17T15:06:00BloodIceMjolnir261262--0.152--
2013-02-21T00:57:00dbaughManual testing262263--0.484--
2015-04-13T20:08:00VictordeHollanderManual testing263264--0.968--
2015-04-13T20:08:00VictordeHollanderManual testing264265--1.843--
2015-10-31T16:44:08ramgeisManual testing265266--3.686--
2016-07-06T22:01:14Gordon SpenceManual testing266267--7.372--
2019-03-20T02:02:07chuenkitManual testing267268--14.74--


ECM factoring results:

Old Calculation Method

Total ECM effort:7.201 GHz-days
Estimated T-Level:4.250
DigitsB1CurvesCompleteFacMiss
201100085 / 1000.85042.559%
255000085 / 2800.30473.778%

New Calculation Method

Total ECM effort:7.201 GHz-days
Estimated T-Level:4.250
DigitsB1CompleteFacMiss
20110002.7426.445%
25500000.24878.051%
302500000.01598.486%


ECM Summary

B1B2factorcurvesGHz-days
500005000000847.117
50000500000010.085


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-07-04T00:00:00ANONYMOUSv4_computers6C2FC3E321FB7BC70.133


PRP results:
dateuseridcompidcofactorsres64PRP
2020-03-28T10:16:05Christoph ZengerManual testing
143025260171480513987287
307CA5E563DC5A04no
2020-03-30T06:56:06Alvin BunkBADCAT
143025260171480513987287
307CA5E563DC5A04no


P-1 factor-bounds graph:
B1 = 4000000, B2 = 200000000 (P-1 stage 2)
B1 = 4000000 (P-1 stage 1)
B1 = 580000, B2 = 15080000 (P-1 stage 2)
B1 = 580000 (P-1 stage 1)
B1 = 200000, B2 = 3500000 (P-1 stage 2)
B1 = 202740 (P-1 stage 1)
B1 = 200000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
102
103
104
105
106
107
102
103
104
105
106
107
108
109
1010
1011
1012
TF factor-bounds graph:
268
267
266
265
264
263
262
261
260
258
250
260
270
280
290
2100
Last modified: 2020-03-30T06:56:06+00:00