is 2 2128303 - 1
has 640684 decimal digits
takes 0.140 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
Actual26713.961367.1642%500000150000000.12305.1615%14.084368.8590%1.6948%
PrimeNet2580.018062.0690%90001600000.00162.6845%0.019763.0872%1.0183%
GPU722620.288764.5161%100001400000.00161.4553%0.290365.0325%0.5164%
Difference+5+13.6727+2.6481%+490000+14860000+0.1214+3.7062%+13.7940+3.8265%+3.8265%

Known prime factors (3 factors, 147.1 bits, 0.00691307% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
212830385132121826.34320
22 × 5
-454.219e-123.865e-77.761e-7
2128303117688387896471443.4202764841
2764841
2008-08-26127648417.986e-70.01440.0268
21283031950055224517588197560232477.36845812443635083637
32 × 23 × 20959 × 10559480549
2021-12-20209591055948054917,17454.850102.44

4 Composite Factors:
exponentprime factorscomposite factordigitsbits*
212830310019062078697219512872269.763
21283031660123373303134850628694051478332103.711
2128303229498855682563815224383095515829388137120.788
212830319537724351329560307903823837808144883085160145147.131
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2016-03-16T11:27:15alpertronManual testing5000001500000012-
skipped known factor: 85132121
skipped known factor: 11768838789647
--0.123--5.161%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2008-08-26T20:20:00ANONYMOUSManual testing??43.420142.47999e-70.3025.36087e-7


ECM factoring results:

Old Calculation Method

Total ECM effort:1.764 GHz-days
Estimated T-Level:1.000
DigitsB1CurvesCompleteFacMiss
201100020 / 1000.20081.791%
255000020 / 2800.07193.094%

New Calculation Method

Total ECM effort:1.764 GHz-days
Estimated T-Level:1.000
DigitsB1CompleteFacMiss
20110000.65352.064%
25500000.05894.325%
302500000.00499.641%


ECM Summary

B1B2factorcurvesGHz-days
50000500000060.511
50000500000070.597
50000620918270.656


Lucas-Lehmer results:
No L-L results for M2128303


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-08T13:39:46Oliver KruseGTX-3
85132121
11768838789647
90D01FE140A7C3__no
2017-11-17T23:13:04kkmrkkblmbrbkc4.xlarge
85132121
11768838789647
90D01FE140A7C3__no
2021-12-20T08:52:19MarkSdesktop-i7
85132121
11768838789647
195005522451758819756023
027F9D9C4909958Dno


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
2
220
230
240
250
260
270
280
290
2100
Last modified: 2022-05-11T01:07:06+00:00