is 2 125921 - 1
has 37906 decimal digits
takes 0.000 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-LE83B1F54B113EC28double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual267235.972774.6269 %10000000020000000000.770511.9233 %236.743277.6522 %
Target2440.000061.3636 %22001800000.00006.1449 %0.000163.7378 %
Difference+23+235.9727+13.2632 %+99997800+1999820000+0.7705+5.7784%+236.7432+13.9144 %

Known prime factors (1 factor, 87.6 bits, 0.06952789% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
1259212265893533422808258332325192787.550899728215874559548579
53 × 19759 × 404531 × 2123824867
2009-08-254045312123824867248,909,5720.43950.8182

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2000-11-25ANONYMOUSv4_computers100000025000000--0.00927.814%
2002-06-02ANONYMOUSv4_computers32768327680012--0.00119.396%
2002-07-20ANONYMOUSv4_computers65536655360012--0.00221.988%
2003-02-09ANONYMOUSv4_computers1310721310720030--0.00324.542%
2003-09-29ANONYMOUSv4_computers2621442621440012--0.00627.050%
2017-03-15kkmrkkblmbrbkManual testing100000000200000000012---41.203%


Trial Factoring results:
5758596061626364656667
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1999-09-22ANONYMOUSv4_computers2522530.005
2000-04-19ANONYMOUSv4_computers212540.019
2022-03-07LordJuliusManual testing254255
2000-12-31ANONYMOUSv4_computers212560.076
2002-06-02ANONYMOUSv4_computers212570.152
2022-03-07LordJuliusManual testing257258
2009-01-02Sturle Sundegiasha.ifi2582590.305
2009-01-26Sturle Sundeginy.ifi2592600.610


ECM factoring results:
Total ECM effort:11.593 GHz-days
Estimated T-Level:30.581
DigitsB1CompleteFacMiss
201100070.2120.000%
255000010.7260.002%
302500001.23729.022%
3510000000.11689.028%
4030000000.00999.076%


ECM Summary

B1B2factorcurvesGHz-days
10.007
5000050000002730.677
250000250000005347.308
1000000100000000673.601


Lucas-Lehmer results:
No L-L results for M125921


PRP results:
dateuseridcompidcofactorsres64
2017-09-21Oliver KruseDoppelherz
226589353342280825833232519
3379FA7682947041
2017-09-22Oliver KruseManual testing
226589353342280825833232519
3379FA7682947041
2017-10-13kkmrkkblmbrbkManual testing
226589353342280825833232519
3379FA7682947041
2020-04-17Oliver KruseAddPrpType5
226589353342280825833232519
BBB0EAEED32FE95F
2024-02-03Wentao HuangManual testing
226589353342280825833232519
BBB0EAEED32FE95F


CERT results:
dateuseridcompid
2024-02-03Naegi Makoto1035G1


P-1 factor-bounds graph:
B1 = 100000000, B2 = 2000000000 (P-1 stage 2)
B1 = 100000000 (P-1 stage 1)
B1 = 1000000, B2 = 25000000 (P-1 stage 2)
B1 = 262144, B2 = 26214400 (P-1 stage 2)
B1 = 1000000 (P-1 stage 1)
B1 = 131072, B2 = 13107200 (P-1 stage 2)
B1 = 65536, B2 = 6553600 (P-1 stage 2)
B1 = 262144 (P-1 stage 1)
B1 = 32768, B2 = 3276800 (P-1 stage 2)
B1 = 131072 (P-1 stage 1)
B1 = 65536 (P-1 stage 1)
B1 = 32768 (P-1 stage 1)
103
104
105
106
107
108
103
104
105
106
107
108
109
1010
TF factor-bounds graph:
260
259
258
257
256
255
254
253
this exponent TF target: 44
TF double-checked to: 67
ECM T-Level=30.58 ~= 85-bit
250
260
270
280
290
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Last modified: 2024-03-03T02:29:32+00:00