is 2 1878733 - 1
has 565555 decimal digits
takes 0.102 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L018D54D34B475A2Cdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26715.815968.6567%500000150000000.10155.0846%15.917470.2504%1.5937%
PrimeNet2570.010263.1579%90001600000.00143.0317%0.011664.2748%1.1169%
GPU722610.163565.5738%100001500000.00141.6912%0.164966.1560%0.5822%
Difference+6+15.6524+3.0829%+490000+14850000+0.1001+3.3934%+15.7525+4.0944%+4.0944%

Known prime factors (3 factors, 199.3 bits, 0.01060884% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
18787331884268785042235911857.38750147327615
5 × 7 × 11 × 3583 × 36353
2003-01-093583363530.01960.00040.0006
18787337923822721479317009932169.425210882087062912
27 × 52709 × 31256831
2020-12-14527093125683178.8640.13790.2502
187873366796175050676359780392272.5001777692068289543
3 × 7 × 84652003251883
2021-10-20784652003251883562.26362,797677,604

4 Composite Factors:
exponentprime factorscomposite factordigitsbits*
187873314930611812291895928250989535142872586339126.812
1878733125861947608206455109402944296962171804940129.887
1878733529281049574459208945475911235263446249272743141.925
187873399730776022754568744628542395773001851313045330474
3619322657
60199.312
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2016-03-16T12:39:09alpertronManual testing5000001500000012-
skipped known factor: 188426878504223591
--0.101--5.085%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2003-01-09T00:00:00ANONYMOUSv4_computers??57.387180.0090.2070.019
2003-08-25T00:00:00ANONYMOUSv4_computers??57.387180.0090.2070.019


ECM factoring results:

Old Calculation Method

Total ECM effort:19.824 GHz-days
Estimated T-Level:24.589
DigitsB1CurvesCompleteFacMiss
2011000257 / 1002.5707.555%
2550000257 / 2800.91839.872%

New Calculation Method

Total ECM effort:19.824 GHz-days
Estimated T-Level:24.589
DigitsB1CompleteFacMiss
20110008.7950.015%
25500000.79745.053%
302500000.04995.187%
3510000000.00299.773%


ECM Summary

B1B2factorcurvesGHz-days
500005000000241.663
50000500000060.416
50000660000020816.25
50000660000050.391
50000668399770.550
50000675000070.553


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1998-12-13T00:00:00ANONYMOUSv4_computers018D54D34B475A2C0.102


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-04T13:16:12Oliver KruseGTX-0
188426878504223591
932F175F7D0217__no
2017-11-08T05:49:13kkmrkkblmbrbkold
188426878504223591
932F175F7D0217__no
2020-12-19T07:12:21M89093871
188426878504223591
792382272147931700993
F27E0649921E29CEno
2021-10-22T12:44:47JackBlockWin10
188426878504223591
792382272147931700993
6679617505067635978039
F27E0649921E29CEno


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
1013
1014
TF factor-bounds graph:
267
2
250
260
270
280
290
2100
Last modified: 2021-10-22T12:44:47+00:00