is 2 1915841 - 1
has 576726 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
Actual26715.509668.6567%500000150000000.10155.0966%15.611170.2542%1.5975%
PrimeNet2570.010063.1579%90001700000.00143.0916%0.011464.2969%1.1390%
GPU722610.160365.5738%100001700000.00151.7608%0.161866.1799%0.6062%
Difference+6+15.3493+3.0829%+490000+14830000+0.1000+3.3359%+15.4493+4.0742%+4.0742%

Known prime factors (2 factors, 107.4 bits, 0.00560426% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
19158412532588534731237.88266096
24 × 35 × 17
-2432431.249e-81.911e-53.890e-5
19158418272863551706539693592169.487215906840695719
34 × 9239 × 288507041
2020-10-309239288507041104.181.23722.3094

1 Composite Factors:
exponentprime factorscomposite factordigitsbits*
191584120951759380437688953547681273380733107.369
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2016-03-17T19:18:56alpertronManual testing5000001500000012-
skipped known factor: 253258853473
--0.101--5.097%


Trial Factoring results:
No TF results for M1915841


ECM factoring results:

Old Calculation Method

Total ECM effort:21.812 GHz-days
Estimated T-Level:24.607
DigitsB1CurvesCompleteFacMiss
2011000258 / 1002.5807.480%
2550000258 / 2800.92139.729%

New Calculation Method

Total ECM effort:21.812 GHz-days
Estimated T-Level:24.607
DigitsB1CompleteFacMiss
20110009.1040.011%
25500000.80844.588%
302500000.05095.120%
3510000000.00299.770%


ECM Summary

B1B2factorcurvesGHz-days
500005000070.293
500005000000342.361
50000500000030.208
50000575000070.515
50000800000021418.43


Lucas-Lehmer results:
No L-L results for M1915841


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-30T15:14:46alpertronManual testing
253258853473
BC8653BC5FB6BB__no
2017-10-20T05:05:12Oliver KruseThreadripper
253258853473
BC8653BC5FB6BB__no
2020-10-30T18:38:20mrhw
253258853473
827286355170653969359
5A570775FCB74A46no


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
101
102
103
104
105
106
101
102
103
104
105
106
107
108
109
TF factor-bounds graph:
267
230
240
250
260
270
280
290
2100
Last modified: 2022-01-25T11:46:55+00:00