is 2 8563 - 1
has 2578 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
Actualunknown4000000004000000000.070729.9725%0.070729.9725%
Target2440.000368.1818%500100000.00001.2048%0.000368.5652%
Difference-44-0.0003-68.1818%+399999500+399990000+0.0707+28.7677%+0.0705-38.5927%

Known prime factors (6 factors, 368.9 bits, 4.30769582% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
856332402393824.9501892
22 × 11 × 43
-11433.679e-102.253e-93.958e-9
85632407806826094871547.77514059364861
20477 × 686593
-204776865930.00341.004e-51.235e-5
85632068583611277037371857.52112078615037236
22 × 3 × 11 × 23 × 50683 × 78497
-50683784972.75459.230e-61.824e-5
85632350351158031669063612167.67113723876900803860
22 × 5 × 7 × 7333 × 13368020203
-7333133680202033,893.20.12880.2405
856391396717491565446719174172582.918533672296458983105916
22 × 3 × 338339 × 131444176910087
-338339131444176910087149,441,4381,266.32,365.1
85633165155740955035253840559592788.03218481582044581544165833
18481582044581544165833
-1184815820445815441658331.320e+101.780e+113.325e+11

57 Composite Factors:
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2021-08-27Seth_TrManual testing100000000100000000-
skipped known factor: 32402393
skipped known factor: 240780682609487
skipped known factor: 206858361127703737
--0.018--26.287%
2021-08-27Seth_TrManual testing400000000400000000-
skipped known factor: 32402393
skipped known factor: 240780682609487
skipped known factor: 206858361127703737
--0.071--29.972%


Trial Factoring results:
No TF results for M8563


ECM factoring results:
Total ECM effort:1,574.608 GHz-days
Estimated T-Level:45.778
DigitsB1CompleteFacMiss
20110003,192.2000.000%
2550000887.2220.000%
30250000232.4420.000%
35100000047.1280.000%
4030000008.0450.032%
45110000001.19230.350%
50440000000.15685.591%
551100000000.01898.190%
602600000000.00299.813%


ECM Summary

B1B2factorcurvesGHz-days
30000003000000002,71120.69
30000006000000001,00010.12
11000000365788846624,8001,544


Lucas-Lehmer results:
No L-L results for M8563


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-21Oliver KruseOliver-PCA72AD74C52EC52__?
2017-09-21Oliver KruseManual testingA72AD74C52EC52__?
2017-10-02kkmrkkblmbrbkManual testing
32402393
240780682609487
206858361127703737
235035115803166906361
9139671749156544671917417
316515574095503525384055959
A72AD74C52EC52__no
2017-12-07ATHManual testing
32402393
240780682609487
206858361127703737
235035115803166906361
9139671749156544671917417
316515574095503525384055959
A72AD74C52EC52__no
2020-04-17Oliver KruseManual testing
32402393
240780682609487
206858361127703737
235035115803166906361
9139671749156544671917417
316515574095503525384055959
B59DCEB21333CD__no


P-1 factor-bounds graph:
B1 = 400000000 (P-1 stage 1)
B1 = 100000000 (P-1 stage 1)
100
101
102
103
104
105
106
107
108
109
100
101
102
103
104
105
106
107
108
109
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
TF factor-bounds graph:
this exponent TF target: 44
TF double-checked to: 67.7
ECM T-Level=45.78 ~= 135-bit
250
260
270
280
290
2100
2110
2120
2130
2140
Last modified: 2023-03-25T13:08:14+00:00