is 2 491 - 1
has 148 decimal digits
takes 0.000 GHz-days to do one PRP test
Has been fully factored.
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L-unknown--unknown-
PRP0C8BE7B51CC65FF1PRP-tested
Cofactor is a certified prime

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actualunknown----0.00000.0000%
Target2440.004879.5455%500800000.00000.4770%0.004879.6430%
Difference-44-0.0048-79.5455%-500-800000.0000-0.4770%-0.0048-79.6430%

Known prime factors (7 factors, 491.0 bits, 100.00000000% known):
Remaining cofactor is a certified-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
49198339.9411
1		-111.384e-131.474e-113.000e-11
4917707719722.8787849
47 × 167		-471671.933e-97.892e-101.410e-9
4911100974363270571546.646112115515608
23 × 34 × 109 × 499 × 3181		-49931810.03099.510e-91.497e-8
49169764470525257186231962.5977104324900739021
7104324900739021		-171043249007390212,498.05,706.010,657
491199709051186231958518905626732994.01220336970589229323678096296
23 × 34 × 31384213872267474811877		-81313842138722674748118778.447e+122.521e+104.708e+10
491371754267643977947378687664391538843937121.4843785685006557820238072175808467809
3785685006557820238072175808467809		-137856850065578202380721758084678093.427e+143.041e+215.679e+21
491
hide decimal representation
14797326616665978116353515926860025681383
41133.442

57 Composite Factors:
P-1 results:
No P-1 results for M491


Trial Factoring results:
No TF results for M491


ECM factoring results:
No ECM results for M491


Lucas-Lehmer results:
No L-L results for M491


PRP results:
dateuseridcompidcofactorsres64PRP
2018-01-24Luke_Richardswork-laptop0C8BE7B51CC65FF1no


P-1 factor-bounds graph:
100
101
102
103
100
101
102
103
104
105
106
107
108
109
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
TF factor-bounds graph:
this exponent TF target: 44
TF double-checked to: 67.8
250
260
270
280
290
2100
2110
2120
2130
Last modified: 2023-06-05T21:50:05+00:00