is 2 1915817 - 1
has 576719 decimal digits
takes 0.104 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
Actual26715.509868.6567%500000150000000.10155.0966%15.611370.2542%1.5974%
PrimeNet2570.010063.1579%90001700000.00143.0916%0.011464.2969%1.1390%
GPU722610.160365.5738%100001700000.00151.7608%0.161866.1799%0.6062%
Difference+6+15.3494+3.0829%+490000+14830000+0.1000+3.3358%+15.4495+4.0742%+4.0742%

Known prime factors (1 factor, 25.8 bits, 0.00134545% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
191581757474511825.77615
3 × 5
-352.341e-122.446e-74.803e-7

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2016-03-17T19:18:56alpertronManual testing5000001500000012-
skipped known factor: 57474511
--0.101--5.097%


Trial Factoring results:
No TF results for M1915817


ECM factoring results:

Old Calculation Method

Total ECM effort:45.403 GHz-days
DigitsB1CurvesCompleteFacMiss
2011000600 / 1006.0000.241%
2550000600 / 2802.14311.687%

New Calculation Method

Total ECM effort:45.403 GHz-days
DigitsB1CompleteFacMiss
201100024.2050.000%
25500002.27810.248%
302500000.14586.508%
3510000000.00799.323%


ECM Summary

B1B2factorcurvesGHz-days
50000500000037025.69
50000670000070.552
50000675000070.554
50000800000021618.61


Lucas-Lehmer results:
No L-L results for M1915817


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-30T15:14:46alpertronManual testing
57474511
5E4D12D0C6680E__no
2017-10-20T05:04:38Oliver KruseThreadripper
57474511
5E4D12D0C6680E__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
TF factor-bounds graph:
267
220
230
240
250
260
270
280
290
2100
Last modified: 2022-01-18T14:10:49+00:00