is 2 2082503 - 1
has 626896 decimal digits
takes 0.137 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L1541C839F8ED769Adouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26957.328569.5652%25000001250000000.87467.2674%58.203171.7770%2.2118%
PrimeNet2580.018463.7931%90001600000.00162.6735%0.020164.7611%0.9680%
GPU722620.295066.1290%90001400000.00151.3992%0.296566.6030%0.4739%
Difference+7+57.0335+3.4362%+2491000+124860000+0.8731+5.8681%+57.9066+5.1741%+5.1741%

Known prime factors (1 factor, 76.7 bits, 0.00368516% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
20825031265087584471501545112972476.74430374207971645216
25 × 7 × 135599142730559
2021-12-243213559914273055911,001704,3361,315,503

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-02-27T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.179%
2009-07-26T12:31:00harleeP4_260020000260000---0.003--0.751%
2010-12-28T02:15:00Jocelyn LaroucheManual testing3000030000---0.003--0.297%
2011-01-07T22:30:00Jocelyn LaroucheManual testing5000050000---0.005--0.435%
2011-01-24T16:22:00James HeinrichQ66001350002936250---0.027--2.431%
2016-07-07T00:37:27Jocelyn LaroucheManual testing182403587250012---0.047--2.999%
2016-11-04T12:39:36Jocelyn Larouchelow 4M218883218883---0.021--1.075%
2016-11-07T03:11:22Jocelyn Larouchelow 4M262659262659---0.025--1.181%
2016-11-11T16:54:52Jocelyn Larouchelow 4M315190315190---0.030--1.294%
2017-04-04T14:33:56mikrMSI250000012500000012---0.875--7.267%
2017-05-13T16:00:17Jocelyn Larouchelow 4M39022839022806---0.055--3.072%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-01-17T00:00:00ANONYMOUSv4_computers21258--0.018--
2016-02-23T16:29:05Mark RoseManual testing258260--0.055--
2009-01-03T11:30:00Sturle Sundekinner.ifi260261--0.074--
2012-03-17T19:48:00Sebastian HornbostelManual testing261262--0.148--
2013-09-02T08:36:00ramgeisManual testing262263--0.471--
2015-03-31T15:56:00VictordeHollanderManual testing263264--0.943--
2015-03-31T15:56:00VictordeHollanderManual testing264265--1.794--
2015-11-05T09:47:18ramgeisManual testing265266--3.588--
2016-09-14T10:22:38Gordon SpenceManual testing266267--7.177--
2019-04-01T03:15:22chuenkitManual testing267268--14.35--
2021-08-26T09:33:33TJAOIManual testing268269--28.71--


ECM factoring results:

Old Calculation Method

Total ECM effort:17.771 GHz-days
Estimated T-Level:23.625
DigitsB1CurvesCompleteFacMiss
2011000203 / 1002.03013.000%
2550000203 / 2800.72548.370%

New Calculation Method

Total ECM effort:17.771 GHz-days
Estimated T-Level:23.625
DigitsB1CompleteFacMiss
20110006.6060.135%
25500000.59755.038%
302500000.03796.385%
3510000000.00299.831%


ECM Summary

B1B2factorcurvesGHz-days
500005000070.355
50000500000019716.75
50000500000050.425
766202417689010.245


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-01-29T00:00:00ANONYMOUSv4_computers1541C839F8ED769A0.137


PRP results:
dateuseridcompidcofactorsres64PRP
2021-12-31T07:20:58GURA LOVE
126508758447150154511297
1F58CF2AD0E09E13no
2021-12-31T17:57:05_p95holder_TFL16_PRPt11-E_b
126508758447150154511297
1F58CF2AD0E09E13no


P-1 factor-bounds graph:
B1 = 2500000, B2 = 125000000 (P-1 stage 2)
B1 = 2500000 (P-1 stage 1)
B1 = 390228, B2 = 3902280 (P-1 stage 2)
B1 = 182403, B2 = 5872500 (P-1 stage 2)
B1 = 390228 (P-1 stage 1)
B1 = 315190 (P-1 stage 1)
B1 = 135000, B2 = 2936250 (P-1 stage 2)
B1 = 262659 (P-1 stage 1)
B1 = 218883 (P-1 stage 1)
B1 = 182403 (P-1 stage 1)
B1 = 135000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 20000, B2 = 260000 (P-1 stage 2)
B1 = 30000 (P-1 stage 1)
B1 = 20000 (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: 2021-12-31T17:57:05+00:00