is 2 20489611 - 1
has 6167988 decimal digits
takes 14.521 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L13BB06700386CB4Bdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual2682.909063.2353%3100003100000.31862.0830%3.227664.0011%
Target2695.826763.7681%150000360000002.16123.7711%7.987965.1345%
Difference-1-2.9177-0.5328%+160000-35690000-1.8427-1.6881%-4.7603-1.1334%

Known prime factors (1 factor, 66.8 bits, 0.00032608% known):
Remaining cofactor is PRP status unknown

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
204896111295831177281832713912166.8123162166371245
5 × 7 × 83 × 271 × 1433 × 2803
2015-02-27143328031.09100.00150.0030

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-12-13ANONYMOUSv4_computers310000310000---0.319--2.083%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2002-10-07ANONYMOUSv4_computers21266--0.721--
2003-01-25ANONYMOUSv4_computers21266--0.721--
2003-02-02ANONYMOUSv4_computers21266--0.721--
2015-02-27NRManual testing266267*66.812210.37033.820.862
2022-04-11LordJuliusManual testing26626766.812210.37033.820.862
2022-04-11LordJuliusManual testing267268--1.459--


ECM factoring results:
No ECM results for M20489611


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2004-11-22ANONYMOUSv4_computers13BB06700386CB4B14.52
2008-03-05dariop2v4_computers13BB06700386CB4B14.52


PRP results:
No PRP results for M20489611


P-1 factor-bounds graph:
B1 = 310000 (P-1 stage 1)
102
103
104
105
106
102
103
104
105
106
TF factor-bounds graph:
268
267
266
this exponent TF target: 69
TF double-checked to: 67.8
250
260
270
Last modified: 2023-06-05T21:50:05+00:00