is 2 1258643 - 1
has 378890 decimal digits
takes 0.040 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L49BC0624B6645452double-checked
PRPC0FFB35542E01A16PRP-tested

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26847.356569.1176%42184751560835650.57418.0921%47.930671.6167%2.4990%
PrimeNet2560.007662.5000%5500900000.00052.4398%0.008163.4149%0.9149%
GPU722600.122065.0000%5500340000.00030.9076%0.122465.3177%0.3177%
Difference+8+47.2344+4.1176%+4212975+156049565+0.5738+7.1846%+47.8082+6.2990%+2.1814%

Known prime factors (1 factor, 125.3 bits, 0.00995128% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
12586435062220060847818307739486502517216899338125.25120109832815372660507147326535472
24 × 251 × 2234269 × 3377347 × 20423587 × 32491637
2022-04-2620423587324916371.364e+110.96881.9102

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-02-24T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.192%
2003-12-13T00:00:00eteov4_computers2000005000000---0.021--3.064%
2014-09-29T22:04:00Jocelyn LaroucheManual testing250994250994---0.012--1.207%
2015-02-01T18:00:00mikrMSI4218475156083565---0.574--8.092%
2022-04-26T03:51:44Sid & AndyPterodactyl360000003600000038125.2511.6540.0803.3096.568%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-07-27T00:00:00ANONYMOUSv4_computers21256--0.008--
2001-11-14T00:00:00ANONYMOUSv4_computers21257--0.015--
2003-06-01T00:00:00ANONYMOUSv4_computers21258--0.031--
2016-02-23T16:28:25Mark RoseManual testing258260--0.092--
2009-02-15T17:24:00Sturle Sundegouffy.ifi260261--0.122--
2011-05-09T14:41:00XyzzyManual testing261262--0.244--
2012-10-11T11:56:00dbaughManual testing262263--0.780--
2015-04-07T08:06:00omylistManual testing263264--1.560--
2015-04-07T21:30:00monstManual testing264265--2.969--
2015-09-23T08:42:45ramgeisManual testing265266--5.937--
2018-09-16T10:11:05YxinityManual testing266267--11.87--
2020-04-30T23:11:16Gordon SpenceManual testing267268--23.75--


ECM factoring results:
Total ECM effort:20.530 GHz-days
Estimated T-Level:25.687
DigitsB1CompleteFacMiss
201100015.1970.000%
25500001.66618.897%
302500000.13787.162%
3510000000.00999.075%


ECM Summary

B1B2factorcurvesGHz-days
50000500000027710.63
500001274659930.182
25000035000000449.71


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2016-06-01T18:50:25MadPooManual testing49BC0624B66454520.040


PRP results:
dateuseridcompidcofactorsres64PRP
2022-04-26T05:16:30aperson12012_VP113
50622200608478183077394865025172168993
C0FFB35542E01A16no


P-1 factor-bounds graph:
B1 = 36000000 (P-1 stage 1)
B1 = 4218475, B2 = 156083565 (P-1 stage 2)
B1 = 4218475 (P-1 stage 1)
B1 = 200000, B2 = 5000000 (P-1 stage 2)
B1 = 250994 (P-1 stage 1)
B1 = 200000 (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: 2022-04-26T05:16:30+00:00