is 2 3892841 - 1
has 1171862 decimal digits
takes 0.486 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 L-L tests remaining
ResidueStatus
L-L1924FD3DA53AF098double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual2677.633067.1642%400001000000.00780.9603%7.640867.4795%0.3153%
PrimeNet2600.039563.3333%170003600000.00653.2467%0.045964.5238%1.1904%
GPU722640.914365.6250%240005000000.00902.2326%0.923466.3925%0.7675%
Difference+3+6.7186+1.5392%+16000-400000-0.0012-1.2723%+6.7174+1.0870%+1.0870%

Known prime factors (4 factors, 268.9 bits, 0.00690638% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
389284112233275082689917111960.086157125285655
5 × 13 × 61 × 1549 × 25583
-1549255830.04300.00050.0006
389284130080706509916571271961.384386359300443
3 × 2683 × 48000907
2016-04-222683480009070.09540.47340.8833
389284162789645355263828009772272.411806475853435368
23 × 3 × 61 × 479 × 25913 × 44381
2019-11-152591344381481.160.00490.0095
3892841371079766942474770853992374.9744766181908565939
3 × 163 × 138497 × 70375483
2021-07-20138497703754831,182.60.71711.2951

11 Composite Factors:
exponentprime factorscomposite factordigitsbits*
3892841367985557417470771318247921331707429737121.469
3892841768123003975485675389281537059177570164740132.497
38928411888756893793437433611868722616906461307941133.795
38928414539520866627758222090201457432677012768941135.060
389284111162341561164824921453668599285510598867342136.358
389284123299966964831944784335271143589294984963482345147.385
389284123105682646102064309388648195007888975849977942673
673188169
59193.880
389284113655199488467172203722349553659057185168704605186
3496889503
60196.443
389284128503490529837684631928086339587272991995285412350
1547763952153
63207.471
389284170087946795986133587719665289479443485478607161168
8900575333521
63208.769
389284185740513313623377933549475547208267570881764488270
3868353879247479263516209444431
81268.854
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2019-11-15T16:37:01Jocelyn LaroucheManual testing400001000002272.4110.0080.9710.0160.960%


P+1 Factoring results:
dateuseridcompidb1b2startfactorSmoothdigitsbits*ghz-days
2021-07-20T08:07:27ATHec2-P_1100000010000000027P-12374.9741.037


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-11-14T00:00:00ANONYMOUSv4_computers?260--0.020--
2016-04-22T15:47:05TJAOIManual testing26126261.384190.0160.9880.033


ECM factoring results:

Old Calculation Method

Total ECM effort:0.537 GHz-days
Estimated T-Level:0.150
DigitsB1CurvesCompleteFacMiss
20110003 / 1000.03097.030%
25500003 / 2800.01198.932%

New Calculation Method

Total ECM effort:0.537 GHz-days
Estimated T-Level:0.150
DigitsB1CompleteFacMiss
20110000.09790.776%
25500000.00999.129%


ECM Summary

B1B2factorcurvesGHz-days
50000500000030.537


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-11-21T00:00:00ANONYMOUSv4_computers1924FD3DA53AF0980.486
1999-10-29T00:00:00curtiscv4_computers1924FD3DA53AF0980.486


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-20T16:57:52kkmrkkblmbrbkManual testing
1223327508268991711
3008070650991657127
B2168E3F96B709__no
2017-12-27T14:05:51Oliver KruseGTX-0
1223327508268991711
3008070650991657127
B2168E3F96B709__no
2019-11-15T21:08:21mnd927016b
1223327508268991711
3008070650991657127
6278964535526382800977
8CE9169207B2A84Dno
2019-11-18T00:48:21arnaudstm-11-010
1223327508268991711
3008070650991657127
6278964535526382800977
8CE9169207B2A84Dno
2021-07-20T09:06:36ATHec2-PRPCF
1223327508268991711
3008070650991657127
6278964535526382800977
37107976694247477085399
8CE9169207B2A84Dno


P-1 factor-bounds graph:
B1 = 1000000, B2 = 100000000 (P-1 stage 2)
B1 = 1000000 (P-1 stage 1)
B1 = 40000, B2 = 100000 (P-1 stage 2)
B1 = 40000 (P-1 stage 1)
102
103
104
105
106
102
103
104
105
106
107
108
TF factor-bounds graph:
267
262
260
250
260
270
280
290
2100
Last modified: 2021-07-20T09:06:36+00:00