is 2 2084921 - 1
has 627624 decimal digits
takes 0.137 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
Actual26714.251868.6567%500000150000000.12305.1487%14.374870.2705%1.6138%
PrimeNet2580.018463.7931%90001600000.00162.6741%0.020164.7613%0.9682%
GPU722620.294766.1290%90001400000.00151.3996%0.296266.6031%0.4740%
Difference+5+13.9572+2.5277%+491000+14860000+0.1214+3.7492%+14.0786+3.6674%+3.6674%

Known prime factors (2 factors, 97.5 bits, 0.00467654% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2084921562928671929.068135
33 × 5
-27273.531e-112.574e-65.239e-6
20849213986543163758364273372168.43495604177898308
22 × 3 × 487 × 16359373357
2022-05-274871635937335746.76184.975158.71

1 Composite Factors:
exponentprime factorscomposite factordigitsbits*
20849212244139445058631365542054791273097.502
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2016-03-16T13:43:05alpertronManual testing5000001500000012-
skipped known factor: 562928671
--0.123--5.149%


Trial Factoring results:
No TF results for M2084921


ECM factoring results:

Old Calculation Method

Total ECM effort:2.832 GHz-days
Estimated T-Level:1.500
DigitsB1CurvesCompleteFacMiss
201100030 / 1000.30073.970%
255000030 / 2800.10789.823%

New Calculation Method

Total ECM effort:2.832 GHz-days
Estimated T-Level:1.500
DigitsB1CompleteFacMiss
20110001.23129.207%
25500000.11389.277%
302500000.00799.282%


ECM Summary

B1B2factorcurvesGHz-days
50000500000060.510
50000645000030.285
50000668440570.677
500006750000141.360


Lucas-Lehmer results:
No L-L results for M2084921


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-06T18:15:48Oliver KruseGTX-3
562928671
0F22470678DE71__no
2017-11-16T21:26:42Chang Chia-Tcheexbpc13
562928671
0F22470678DE71__no
2022-05-30T04:54:35SRJ2877LTOS
562928671
398654316375836427337
9F81E6517753B33Dno


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
220
230
240
250
260
270
280
290
2100
Last modified: 2022-06-17T20:03:34+00:00