5^521-1

Open composite · C364

NFS Planning

GNFS Murphy estimate: 1.72e-24
SNFS Murphy score: 2.91e-17
Preferred method: SNFS
SNFS possible: Yes
SNFS degree: 7
SNFS skew: 1.58008

Identifiers

Target expression: 5^521-1
Target link: FactorDB page
Target ID: 1000000000018437139
Target changed: -
Parent query: Same as target
Parent ID: -
Cofactor token: C364
Imported: Jun 03, 2026, 04:30 PM UTC

Raw pmain126 Factorization

(1) C364

SNFS Polynomial

Polynomial

Degree: 7
Murphy: 2.91e-17
Skew: 1.58008
Selected: Best

n: 3641767935156350948872541657940885662781480241504104928843514811135878117710018703582116645703333888360113087527263721412799183640246729814690510170699260103262334371249404969480080114387907843233128200373566364631549910771771731992202972081544542354637482275031909284832620145672127260081056451624723413987777664710204593824863228412880289397435262799263000488281
# 5^521-1, difficulty: 364.16, skewness: 1.99
# cost: 1.92567e+22, est. time: 9169860.40 GHz days (not accurate yet!)
# Optimized skew: 1.58008 Murphy: 2.91e-17
skew: 1.58008
c7: 1
c0: -125
Y1: -5293955920339377119177015629247762262821197509765625
Y0: 1
type: snfs