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M3745867 Mersenne number exponent details
is 2 3745867 - 1
has 1127619 decimal digits
takes 0.393 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LDA51EF3D494582F1double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual2677.932567.1642%5000001303648501.15377.7719%9.086169.7162%2.5520%
PrimeNet2600.041063.3333%160003200000.00503.0902%0.046064.4664%1.1331%
GPU722640.950265.6250%220004500000.00692.1103%0.957166.3504%0.7254%
Difference+3+6.9823+1.5392%+478000+129914850+1.1468+5.6617%+8.1290+3.3658%+3.3658%

Known prime factors (1 factor, 101.8 bits, 0.00271848% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
3745867450853043305558232373098822829731101.831601800655636676679088044
22 × 3 × 13933 × 1076587 × 1089709 × 3068083
2015-11-14108970930680834.193e+100.18240.3377

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2009-07-07T04:44:00Carsten Kossendeyleela20000265000---0.005--1.150%
2013-03-14T05:30:00Squeeky_SquirrelT7500_22001100002035000---0.033--2.956%
2015-11-14T16:16:38mikrMSI1600000660000001231101.8310.7780.7871.5567.948%
2022-05-17T01:12:23Jocelyn LaroucheManual testing500000130364850---1.154--7.772%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1997-11-29T00:00:00ANONYMOUSv4_computers21260--0.041--
2009-03-05T16:15:00S485122USB-A260261--0.041--
2011-05-06T21:14:00markrManual testing21262--0.164--
2012-05-10T01:21:00GrunwalderGIMPManual testing21263--0.426--
2015-01-23T13:17:00VictordeHollanderManual testing263264--0.524--
2015-01-23T13:17:00VictordeHollanderManual testing264265--0.997--


ECM factoring results:

Old Calculation Method

Total ECM effort:0.897 GHz-days
Estimated T-Level:0.300
DigitsB1CurvesCompleteFacMiss
20110006 / 1000.06094.148%
25500006 / 2800.02197.876%

New Calculation Method

Total ECM effort:0.897 GHz-days
Estimated T-Level:0.300
DigitsB1CompleteFacMiss
20110000.19482.403%
25500000.01798.266%
302500000.00199.892%


ECM Summary

B1B2factorcurvesGHz-days
50000500000060.897


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-01-05T00:00:00ANONYMOUSv4_computersDA51EF3D494582F10.393
1999-12-23T00:00:00ANONYMOUSv4_computersDA51EF3D494582F10.393


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-20T06:17:52kkmrkkblmbrbkManual testing
4508530433055582323730988228297
7433BA64195294__no
2017-12-04T02:29:40Oliver KruseThreadripper
4508530433055582323730988228297
7433BA64195294__no


P-1 factor-bounds graph:
B1 = 500000, B2 = 130364850 (P-1 stage 2)
B1 = 1600000, B2 = 66000000 (P-1 stage 2)
B1 = 1600000 (P-1 stage 1)
B1 = 500000 (P-1 stage 1)
B1 = 110000, B2 = 2035000 (P-1 stage 2)
B1 = 110000 (P-1 stage 1)
B1 = 20000, B2 = 265000 (P-1 stage 2)
B1 = 20000 (P-1 stage 1)
103
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109
TF factor-bounds graph:
267
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263
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2100