is 2 1951837 - 1
has 587562 decimal digits
takes 0.106 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
-unknown- primality tests remaining
ResidueStatus
L-L-unknown--unknown-
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26715.223668.6567%500000150000000.10155.1081%15.325070.2578%1.6010%
PrimeNet2580.019763.7931%80001400000.00122.4672%0.020964.6864%0.8933%
GPU722620.314866.1290%8000900000.00101.1533%0.315766.5197%0.3906%
Difference+5+14.9088+2.5277%+492000+14910000+0.1005+3.9547%+15.0093+3.7381%+3.7381%

Known prime factors (4 factors, 208.4 bits, 0.01067492% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
195183758555111825.80315
3 × 5
-352.298e-122.446e-74.803e-7
195183724322036040711341.145623055
3 × 5 × 73 × 569
2008-07-15735692.792e-77.868e-61.169e-5
195183777287247676673345691962.7451979859170532
22 × 3 × 43 × 6043 × 634939
2015-10-0360436349390.31610.00320.0051
19518374786984252770240850406892478.663122627664419985912
23 × 3 × 11 × 1283 × 362041098101
2020-11-24128336204109810145,7011,551.62,898.0

11 Composite Factors:
exponentprime factorscomposite factordigitsbits*
19518371424179520109774568812166.949
19518374525563366592099867619321592788.548
19518371879783223479329327029996743039932103.890
19518372803023942762135104923098391147932104.467
1951837116429203522189026622543498248104491937119.809
1951837110070915306769934949796759618339821928940129.694
1951837369972837568188688942270885043771054127804143141.408
19518376817524935883369416864989642246064062803100944145.612
195183721663800570790258749959144265806253933040577261755
1
51167.212
195183789984926894172319646476759146263088843863195346905
04911
55182.554
195183752690773826151454300269273907297004024552710723527
0865709650121
63208.357
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2015-10-03T22:21:33alpertronManual testing50000015000000121962.7450.1010.2120.2035.108%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2008-07-15T07:48:00J FeitsmaManual testing??41.145131.29135e-70.2352.86338e-7


ECM factoring results:

Old Calculation Method

Total ECM effort:20.988 GHz-days
Estimated T-Level:24.607
DigitsB1CurvesCompleteFacMiss
2011000258 / 1002.5807.480%
2550000258 / 2800.92139.729%

New Calculation Method

Total ECM effort:20.988 GHz-days
Estimated T-Level:24.607
DigitsB1CompleteFacMiss
20110009.0780.011%
25500000.80644.655%
302500000.05095.125%
3510000000.00299.770%


ECM Summary

B1B2factorcurvesGHz-days
500004610683140.944
500005000000181.253
50000500000050.348
50000675000070.556
50000750000021417.89


Lucas-Lehmer results:
No L-L results for M1951837


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-30T15:28:59alpertronManual testing
58555111
2432203604071
7728724767667334569
130C3867B1B189__no
2017-10-20T12:23:16Oliver KruseGTX-0
58555111
2432203604071
7728724767667334569
130C3867B1B189__no
2020-11-25T11:03:43rbanovccg_lnx01
58555111
2432203604071
7728724767667334569
478698425277024085040689
5D3B04A44271756Dno


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
100
101
102
103
104
105
106
100
101
102
103
104
105
106
107
108
109
1010
1011
1012
TF factor-bounds graph:
267
2
220
230
240
250
260
270
280
290
2100
Last modified: 2022-05-12T09:17:36+00:00