is 2 2784653 - 1
has 838265 decimal digits
takes 0.215 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L0C17C4486C02742Edouble-checked
PRP2DA15A5C4740C353PRP-tested

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26821.404867.6471%3000000900000000.86687.8324%22.271670.1811%2.5340%
PrimeNet2590.027662.7119%120002200000.00262.8589%0.030263.7779%1.0660%
GPU722630.573165.0794%150002400000.00311.7480%0.576265.6898%0.6104%
Difference+5+20.8316+2.5677%+2985000+89760000+0.8638+6.0844%+21.6954+4.4913%+1.9236%

Known prime factors (1 factor, 71.9 bits, 0.00258140% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
278465343542956002736251819512271.883781838096214075
3 × 52 × 36847 × 282913343
2021-06-0236847282913343268.151.73013.2241

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-11-17T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.242%
2010-11-11T04:19:00Jocelyn LaroucheManual testing1500015000---0.002--0.211%
2010-11-25T11:11:00markrtiny1000002075000---0.023--2.483%
2014-10-28T23:25:00Jocelyn LaroucheManual testing123049123049---0.014--0.946%
2016-05-03T01:41:41Jocelyn LaroucheManual testing20000036000006---0.043--3.183%
2017-07-20T22:03:20Jocelyn Larouchelow 4M40000040000006---0.067--3.575%
2019-11-16T23:19:07BigBrotherWinston30000009000000012---0.867--7.832%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2016-02-23T16:29:21Mark RoseManual testing21260--0.055--
2009-02-01T01:15:00Sturle Sundegaudi.ifi260261--0.055--
2012-03-09T02:14:00Grant McCrackenthumper261262--0.110--
2013-01-14T12:31:00dbaughManual testing262263--0.353--
2015-04-21T09:20:00VictordeHollanderManual testing263264--0.705--
2015-04-21T09:20:00VictordeHollanderManual testing264265--1.342--
2016-02-08T11:13:52ramgeisManual testing265266--2.684--
2017-10-19T22:32:31Gordon SpenceManual testing266267--5.367--
2019-02-25T02:38:33chuenkitManual testing267268--10.73--


ECM factoring results:
Total ECM effort:9.368 GHz-days
Estimated T-Level:21.601
DigitsB1CompleteFacMiss
20110003.4623.138%
25500000.32072.594%
302500000.02098.000%


ECM Summary

B1B2factorcurvesGHz-days
500005000000899.264
50000500000010.104


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-11-07T00:00:00ANONYMOUSv4_computers0C17C4486C02742E0.215
1999-05-02T00:00:00ANONYMOUSv4_computers0C17C4486C02742E0.215
2018-08-26T19:08:32kkmrkkblmbrbkold0C17C4486C02742E0.215


PRP results:
dateuseridcompidcofactorsres64PRP
2021-06-03T08:17:04kutenscapella
4354295600273625181951
2DA15A5C4740C353no


P-1 factor-bounds graph:
B1 = 3000000, B2 = 90000000 (P-1 stage 2)
B1 = 3000000 (P-1 stage 1)
B1 = 400000, B2 = 4000000 (P-1 stage 2)
B1 = 400000 (P-1 stage 1)
B1 = 200000, B2 = 3600000 (P-1 stage 2)
B1 = 100000, B2 = 2075000 (P-1 stage 2)
B1 = 200000 (P-1 stage 1)
B1 = 123049 (P-1 stage 1)
B1 = 100000 (P-1 stage 1)
B1 = 15000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
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109
TF factor-bounds graph:
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265
264
263
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2100
Last modified: 2021-06-03T08:17:04+00:00