is 2 1861831 - 1
has 560467 decimal digits
takes 0.101 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LDFD471CF76F5B4F0double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26715.959568.6567%500000150000000.10155.0791%16.061070.2487%1.5920%
PrimeNet2570.010363.1579%90001600000.00143.0267%0.011764.2730%1.1151%
GPU722610.165065.5738%90001500000.00131.6331%0.166366.1360%0.5622%
Difference+6+15.7945+3.0829%+491000+14850000+0.1002+3.4460%+15.8947+4.1127%+4.1127%

Known prime factors (1 factor, 63.9 bits, 0.00343348% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
1861831175200790590121158712063.9264705066963385
5 × 17 × 55353728981
2009-07-2117553537289811.5294237.23443.08

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2016-03-16T12:37:06alpertronManual testing5000001500000012---0.101--5.079%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2003-01-09T00:00:00ANONYMOUSv4_computers21258--0.021--


ECM factoring results:

Old Calculation Method

Total ECM effort:20.273 GHz-days
Estimated T-Level:24.714
DigitsB1CurvesCompleteFacMiss
2011000264 / 1002.6407.042%
2550000264 / 2800.94338.886%

New Calculation Method

Total ECM effort:20.273 GHz-days
Estimated T-Level:24.714
DigitsB1CompleteFacMiss
201100010.8780.002%
25500001.00136.743%
302500000.06493.843%
3510000000.00399.702%


ECM Summary

B1B2factorcurvesGHz-days
10.00000e+0
500005000000382.630
50000660000021917.09
50000675000070.552


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-03-01T00:00:00ANONYMOUSv4_computersDFD471CF76F5B4F00.101


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-04T08:54:44Oliver KruseGTX-2
17520079059012115871
903F190E578609__no
2017-11-07T12:23:13kkmrkkblmbrbkold
17520079059012115871
903F190E578609__no


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
TF factor-bounds graph:
267
258
250
260
270
280
290
2100
Last modified: 2021-09-17T08:21:47+00:00