is 2 3915521 - 1
has 1178690 decimal digits
takes 0.488 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L788D99CE80C0FACBdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual271122.098369.0141%520000016049353320159.024312.5637%281.122672.9070%
Target2640.909065.6250%2600025000000.02912.2795%0.938166.4086%
Difference+7+121.1892+3.3891%+5174000+16046853320+158.9953+10.2841%+280.1845+6.4985%

Known prime factors (1 factor, 146.0 bits, 0.00372851% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
39155218863341285081672451029627905903340887927879344145.99111318214466327306699452803223253483876
22 × 11 × 23 × 2647 × 2797 × 2861 × 51683 × 112349 × 1539943 × 59048867		2023-07-011539943590488673.966e+100.84511.0867

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2009-07-10Carsten Kossendeyleela20000285000---0.006--0.646%
2011-10-04Squeeky_SquirrelT7500_2200700001172500---0.024--1.443%
2014-11-03Jocelyn LaroucheManual testing8639286392---0.016--0.529%
2016-04-09Jocelyn LaroucheManual testing22809641057286---0.079--2.525%
2021-11-18Aaron HavilandManual testing5000001500000012---0.233--3.759%
2022-04-28Jocelyn LaroucheManual testing500000130364850---1.370--5.421%
2022-10-30Jocelyn LaroucheManual testing1000000130364850---1.455--5.973%
2023-02-12Jocelyn LaroucheManual testing1000000263698050---2.769--6.612%
2023-07-01Sid & AndyMagic_8_Ball52000001604935332044145.991159.00.977318.012.564%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-11-10ANONYMOUSv4_computers21260--0.039--
2009-02-23S485122USB-A260261--0.039--
2011-02-17Grant McCrackenthumper261262--0.078--
2012-02-10GrunwalderGIMPManual testing21263--0.408--
2016-02-23Mark RoseManual testing262263--0.251--
2015-01-14VictordeHollanderManual testing263264--0.501--
2015-01-14VictordeHollanderManual testing264265--0.954--
2016-02-11ramgeisManual testing265266--1.908--
2016-12-03Gordon SpenceManual testing266267--3.817--
2019-01-11YxinityManual testing267268--7.634--
2020-05-22TJAOIManual testing268269--15.27--
2021-04-18axnManual testing269270--30.54--
2021-06-09-Anonymous-Manual testing270271--61.07--


ECM factoring results:
Total ECM effort:9.730 GHz-days
Estimated T-Level:20.747
DigitsB1CompleteFacMiss
20110001.59220.361%
25500000.14986.122%
302500000.00999.056%


ECM Summary

B1B2factorcurvesGHz-days
500005000000254.477
50000640000071.418
500002702353573.834


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-01-13ckprimev4_computers788D99CE80C0FACB0.488
1999-12-08ANONYMOUSv4_computers788D99CE80C0FACB0.488


PRP results:
dateuseridcompidcofactorsres64PRP
2023-07-01Naegi Makoto5950X
88633412850816724510296279059033408879278793
0E8A2877C8821429no


P-1 factor-bounds graph:
B1 = 5200000, B2 = 16049353320 (P-1 stage 2)
B1 = 1000000, B2 = 263698050 (P-1 stage 2)
B1 = 1000000, B2 = 130364850 (P-1 stage 2)
B1 = 500000, B2 = 130364850 (P-1 stage 2)
B1 = 5200000 (P-1 stage 1)
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 1000000 (P-1 stage 1)
B1 = 500000 (P-1 stage 1)
B1 = 228096, B2 = 4105728 (P-1 stage 2)
B1 = 228096 (P-1 stage 1)
B1 = 70000, B2 = 1172500 (P-1 stage 2)
B1 = 86392 (P-1 stage 1)
B1 = 70000 (P-1 stage 1)
B1 = 20000, B2 = 285000 (P-1 stage 2)
B1 = 20000 (P-1 stage 1)
103
104
105
106
107
103
104
105
106
107
108
109
1010
1011
TF factor-bounds graph:
271
270
269
268
267
266
265
264
263
262
261
260
this exponent TF target: 64
TF double-checked to: 67.9
ECM T-Level=20.75 ~= 52-bit
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290
2100
2110
2120
2130
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Last modified: 2023-09-25T11:53:03+00:00