is 2 2186651 - 1
has 658248 decimal digits
takes 0.144 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L42E5F8628CEC1987double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26713.588867.1642%500000150000000.12305.1783%13.711868.8645%1.7003%
PrimeNet2580.017662.0690%100001800000.00182.8599%0.019463.1537%1.0848%
GPU722620.281064.5161%110001600000.00181.5697%0.282865.0731%0.5570%
Difference+5+13.3078+2.6481%+489000+14840000+0.1212+3.6086%+13.4290+3.7914%+3.7914%

Known prime factors (1 factor, 78.3 bits, 0.00357992% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
21866513670566817960380774622492478.28083931245040026524
22 × 72 × 2845639 × 150483121
2008-12-25284563915048312153,1071.03821.4599

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-03-16T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.280%
2016-03-28T11:47:17alpertronManual testing5000001500000012---0.123--5.178%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-01-29T00:00:00ANONYMOUSv4_computers21258--0.018--


ECM factoring results:

Old Calculation Method

Total ECM effort:1.551 GHz-days
Estimated T-Level:0.850
DigitsB1CurvesCompleteFacMiss
201100017 / 1000.17084.294%
255000017 / 2800.06194.099%

New Calculation Method

Total ECM effort:1.551 GHz-days
Estimated T-Level:0.850
DigitsB1CompleteFacMiss
20110000.67650.850%
25500000.06393.921%
302500000.00499.604%


ECM Summary

B1B2factorcurvesGHz-days
10.00000e+0
500005000000100.855
50000696826670.696


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-02-14T00:00:00ANONYMOUSv4_computers42E5F8628CEC19870.144


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-09T05:51:52Oliver KruseGTX-3
367056681796038077462249
993EF7EDD45C5B__no
2017-11-19T10:21:34kkmrkkblmbrbkc4.xlarge
367056681796038077462249
993EF7EDD45C5B__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)
102
103
104
105
106
107
102
103
104
105
106
107
108
109
TF factor-bounds graph:
267
258
250
260
270
280
290
2100
Last modified: 2022-07-05T11:56:34+00:00