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M3785531 Mersenne number exponent details
is 2 3785531 - 1
has 1139559 decimal digits
takes 0.398 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L02F98421BD2397F7double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual2677.849367.1642%5000001303648501.15377.7809%9.003069.7191%2.5549%
PrimeNet2600.040663.3333%170003400000.00533.1858%0.045864.5015%1.1681%
GPU722640.940265.6250%240004500000.00722.1617%0.947466.3681%0.7431%
Difference+3+6.9091+1.5392%+476000+129914850+1.1465+5.6192%+8.0556+3.3510%+3.3510%

Known prime factors (1 factor, 105.5 bits, 0.00278603% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
37855315602754326289761504025090922000132105.4667400222487003489740310000
24 × 3 × 54 × 7 × 192 × 59 × 73 × 109 × 22669 × 9172433
2016-04-122266991724334.316e+100.07940.1421

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2009-07-14T21:28:00Carsten Kossendeydurandal20000265000---0.005--1.152%
2012-04-17T19:03:00Squeeky_SquirrelP4_26001100002062500---0.033--2.970%
2016-04-12T13:43:38mikrMSI1600000660000001232105.4660.7780.7951.5567.956%
2022-05-17T01:12:22Jocelyn LaroucheManual testing500000130364850-
skipped known factor: 56027543262897615040250909220001
--1.154--7.781%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-09-20T00:00:00ANONYMOUSv4_computers21260--0.041--
2009-03-01T22:41:00S485122USB-Z260261--0.041--
2011-04-12T17:16:00markroldgamer261262--0.081--
2012-03-23T23:43:00GrunwalderGIMPManual testing21263--0.422--
2016-02-23T16:29:39Mark RoseManual testing262263--0.259--
2015-01-27T16:51:00VictordeHollanderManual testing263264--0.519--
2015-01-27T16:51:00VictordeHollanderManual testing264265--0.987--
2016-03-02T09:22:00ramgeisManual testing265266--1.974--


ECM factoring results:

Old Calculation Method

Total ECM effort:1.348 GHz-days
Estimated T-Level:0.450
DigitsB1CurvesCompleteFacMiss
20110009 / 1000.09091.352%
25500009 / 2800.03296.831%

New Calculation Method

Total ECM effort:1.348 GHz-days
Estimated T-Level:0.450
DigitsB1CompleteFacMiss
20110000.29074.802%
25500000.02697.410%
302500000.00299.839%


ECM Summary

B1B2factorcurvesGHz-days
50000500000091.348


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-09-27T00:00:00ANONYMOUSv4_computers02F98421BD2397F70.398
1999-11-17T00:00:00Charlie Dorianv4_computers02F98421BD2397F70.398


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-20T19:17:49kkmrkkblmbrbkManual testing
56027543262897615040250909220001
354AAE01ECF8C6__no
2017-12-08T20:40:18Oliver KruseGTX-2
56027543262897615040250909220001
354AAE01ECF8C6__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 = 2062500 (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
104
105
106
107
103
104
105
106
107
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109
TF factor-bounds graph:
267
266
265
264
263
262
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2100