is 2 56123 - 1
has 16895 decimal digits
takes 0.000 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L-unknown--unknown-
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual267529.442876.1194%62000000077248347649473072,384.855830.8137%72,914.298583.4779%
Target2440.000063.6364%500500000.00002.1085%0.000064.4031%
Difference+23+529.4427+12.4830%+619999500+772483476444730+72,384.8557+28.7052%+72,914.2985+19.0748%

Known prime factors (3 factors, 83.5 bits, 0.14869601% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
56123112247616.7761
1
-111.556e-131.720e-93.500e-9
5612332326849824.946288
25 × 32
2008-08-26994.231e-111.548e-83.150e-8
5612336476807112011341.73032497200
24 × 34 × 52 × 17 × 59
2008-08-2681815.355e-61.393e-72.835e-7

4 Composite Factors:
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2016-10-02kkmrkkblmbrbkManual testing100000000200000000012-
skipped known factor: 112247
skipped known factor: 32326849
skipped known factor: 3647680711201
--0.350--11.231%
2023-04-23JacobZGreatLakes620000000772483476494730-
skipped known factor: 112247
skipped known factor: 32326849
skipped known factor: 3647680711201
--72,385--30.814%


P+1 Factoring results:
dateuseridcompidb1b2startfactorSmoothdigitsbits*ghz-days
2021-05-03ATHcolab-Pp215000000150000000027--0.176


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2008-08-26ANONYMOUSManual testing??24.94682.48252e-120.0006.58760e-12
2008-08-26ANONYMOUSManual testing??41.730131.35579e-70.0003.38509e-7


ECM factoring results:
Total ECM effort:62.523 GHz-days
Estimated T-Level:32.363
DigitsB1CompleteFacMiss
2011000158.0320.000%
255000028.9920.000%
302500004.0911.672%
3510000000.47362.337%
4030000000.04695.526%
45110000000.00499.624%


ECM Summary

B1B2factorcurvesGHz-days
5000050000002810.348
250000250000005843.613
100000010000000045211.19
1000000312500000010.268
100000032674125565013.99
182746691891049254333.12


Lucas-Lehmer results:
No L-L results for M56123


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-21Oliver KruseOliver-PC
112247
32326849
3647680711201
A0A9EC3B7504CA__no
2017-09-21Oliver KruseManual testing
112247
32326849
3647680711201
A0A9EC3B7504CA__no
2017-10-13kkmrkkblmbrbkManual testing
112247
32326849
3647680711201
A0A9EC3B7504CA__no
2020-04-17Oliver KruseAddPrpType5
112247
32326849
3647680711201
A96E72C2A13161__no
2022-05-12Jorge CoveiroManual testing
112247
A96E72C2A1316196no


P-1 factor-bounds graph:
B1 = 620000000, B2 = 772483476494730 (P-1 stage 2)
B1 = 620000000 (P-1 stage 1)
B1 = 100000000, B2 = 2000000000 (P-1 stage 2)
B1 = 100000000 (P-1 stage 1)
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1010
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TF factor-bounds graph:
2
this exponent TF target: 44
TF double-checked to: 67.9
ECM T-Level=32.36 ~= 91-bit
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Last modified: 2023-12-01T03:39:48+00:00