is 2 2108941 - 1
has 634855 decimal digits
takes 0.139 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L62F39F389148A3C6double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26714.089567.1642%500000150000000.12305.1558%14.212568.8571%1.6930%
PrimeNet2580.018262.0690%90001600000.00162.6799%0.019863.0855%1.0165%
GPU722620.291364.5161%100001400000.00161.4526%0.292965.0316%0.5154%
Difference+5+13.7982+2.6481%+490000+14860000+0.1214+3.7033%+13.9195+3.8256%+3.8256%

Known prime factors (1 factor, 65.8 bits, 0.00311843% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2108941627357833220891739932065.76614873764444356
22 × 3 × 683 × 1814758961
2008-12-1368318147589614.91369.426417.606

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-02-27T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.277%
2016-03-17T11:24:15alpertronManual testing5000001500000012---0.123--5.156%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-01-17T00:00:00Ethan O'Connorv4_computers21258--0.018--


ECM factoring results:

Old Calculation Method

Total ECM effort:2.217 GHz-days
Estimated T-Level:1.200
DigitsB1CurvesCompleteFacMiss
201100024 / 1000.24078.568%
255000024 / 2800.08691.772%

New Calculation Method

Total ECM effort:2.217 GHz-days
Estimated T-Level:1.200
DigitsB1CompleteFacMiss
20110000.96837.986%
25500000.09091.435%
302500000.00699.434%


ECM Summary

B1B2factorcurvesGHz-days
10.00000e+0
500005000000100.851
50000675000070.681
50000682318970.685


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1997-11-21T00:00:00DLv4_computers62F39F389148A3C60.139
1999-02-07T00:00:00Ethan O'Connorv4_computers62F39F389148A3C60.139


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-07T03:18:45Oliver KruseGTX-2
62735783322089173993
0F595078646760__no
2017-11-17T06:43:01ATHec2-1xf
62735783322089173993
0F595078646760__no


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
101
102
103
104
105
106
101
102
103
104
105
106
107
108
109
1010
TF factor-bounds graph:
267
258
250
260
270
280
290
2100
Last modified: 2022-06-15T23:49:06+00:00