is 2 1866211 - 1
has 561786 decimal digits
takes 0.101 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
Actual26715.922168.6567%500000150000000.10155.0806%16.023570.2491%1.5924%
PrimeNet2570.010363.1579%90001600000.00143.0280%0.011664.2735%1.1156%
GPU722610.164665.5738%100001500000.00141.6889%0.166066.1552%0.5814%
Difference+6+15.7575+3.0829%+490000+14850000+0.1001+3.3916%+15.8575+4.0939%+4.0939%

Known prime factors (4 factors, 170.6 bits, 0.00914260% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
1866211134367193927.00236
22 × 32
-999.656e-127.080e-71.441e-6
1866211138584828871133.6903713
47 × 79
2008-07-1547791.106e-93.834e-67.524e-6
18662113073313599031238.16182341
32 × 7 × 1307
2008-07-15913073.577e-86.271e-61.044e-5
186621140193935886674578790092271.7671076886158282064
24 × 32 × 132 × 151 × 293051299
2020-10-12169293051299357.351.25602.3458

11 Composite Factors:
exponentprime factorscomposite factordigitsbits*
186621118621254447647261911960.692
1866211412952521510388622792065.163
186621142591463918541634799612271.851
18662115400746340714429256481729517373098.769
18662115722895452495220121654713194733098.853
18662115570269726466548215003954301898332105.458
1866211123528569759056923959780800797612734109.928
1866211748461507398187892049241823446349142471940132.459
186621116598187173829165199690191098467379600151142136.930
18662111711918570061476093955482504124871553403864944143.619
186621123002569290373438018140245103986991211642692196422
57
52170.620
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2016-03-16T12:37:32alpertronManual testing5000001500000012-
skipped known factor: 134367193
skipped known factor: 13858482887
skipped known factor: 307331359903
--0.101--5.081%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2008-07-15T07:47:00J FeitsmaManual testing??33.690114.92806e-100.2161.05232e-9
2008-07-15T07:47:00J FeitsmaManual testing??38.161121.61435e-80.2163.44722e-8


ECM factoring results:

Old Calculation Method

Total ECM effort:19.818 GHz-days
Estimated T-Level:24.589
DigitsB1CurvesCompleteFacMiss
2011000257 / 1002.5707.555%
2550000257 / 2800.91839.872%

New Calculation Method

Total ECM effort:19.818 GHz-days
Estimated T-Level:24.589
DigitsB1CompleteFacMiss
20110008.7980.015%
25500000.79845.041%
302500000.04995.185%
3510000000.00299.773%


ECM Summary

B1B2factorcurvesGHz-days
500005000000261.800
50000500000030.208
50000660000021416.71
500006750000141.105


Lucas-Lehmer results:
No L-L results for M1866211


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-04T10:17:30Oliver KruseGTX-3
134367193
13858482887
307331359903
58DAEB97538AEC__no
2017-11-07T16:02:38Chang Chia-Tcheexbpc13
134367193
13858482887
307331359903
58DAEB97538AEC__no
2020-10-12T15:56:57mrh.orgx
134367193
13858482887
307331359903
4019393588667457879009
F6D76C550FB68FE7no


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
TF factor-bounds graph:
267
2
220
230
240
250
260
270
280
290
2100
Last modified: 2021-08-27T10:08:41+00:00