is 2 1916741 - 1
has 576997 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
Actual26715.502368.6567%500000150000000.10155.0969%15.603870.2543%1.5975%
PrimeNet2570.010063.1579%90001700000.00143.0919%0.011464.2970%1.1391%
GPU722610.160365.5738%100001700000.00151.7609%0.161766.1800%0.6062%
Difference+6+15.3421+3.0829%+490000+14830000+0.1000+3.3360%+15.4421+4.0743%+4.0743%

Known prime factors (2 factors, 106.0 bits, 0.00553072% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
191674156275515771032.3901468
22 × 367
-43673.934e-101.870e-62.912e-6
1916741145122867303124312713612373.6203785667111600480
25 × 33 × 5 × 876311831389
2021-04-19328763118313891,386.83,755.77,014.5

1 Composite Factors:
exponentprime factorscomposite factordigitsbits*
19167418166864207504589630385171048629732106.010
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2016-03-17T19:18:57alpertronManual testing5000001500000012-
skipped known factor: 5627551577
--0.101--5.097%


Trial Factoring results:
No TF results for M1916741


ECM factoring results:

Old Calculation Method

Total ECM effort:20.867 GHz-days
Estimated T-Level:24.607
DigitsB1CurvesCompleteFacMiss
2011000258 / 1002.5807.480%
2550000258 / 2800.92139.729%

New Calculation Method

Total ECM effort:20.867 GHz-days
Estimated T-Level:24.607
DigitsB1CompleteFacMiss
20110009.0550.012%
25500000.80544.709%
302500000.05095.132%
3510000000.00299.771%


ECM Summary

B1B2factorcurvesGHz-days
500005000000271.875
500005000000191.319
50000750000021217.67


Lucas-Lehmer results:
No L-L results for M1916741


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-30T15:14:49alpertronManual testing
5627551577
DCC7C0C3948EE9__no
2017-10-20T06:22:07Oliver KruseGTX-1
5627551577
DCC7C0C3948EE9__no
2021-04-19T15:04:46XZT800G3Mini2
5627551577
14512286730312431271361
C8B55F9F046C29E3no


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
1012
TF factor-bounds graph:
267
230
240
250
260
270
280
290
2100
Last modified: 2022-03-03T12:26:25+00:00