2^1217-1

Open composite · C248

NFS Planning

GNFS Murphy estimate: 9.22e-18
SNFS Murphy score: 2.82e-17
Preferred method: Similar
SNFS possible: Yes
SNFS degree: 7
SNFS skew: 1.39491

Identifiers

Target expression: 2^1217-1
Target link: FactorDB page
Target ID: 1000000000000001217
Target changed: -
Parent query: Same as target
Parent ID: -
Cofactor token: C248
Imported: Jun 03, 2026, 04:29 PM UTC

Raw pmain126 Factorization

1045741327.6116773272167843384976777858063213917010557325918356879.22053390021902056444354293154701006674049109757797668799.C248

SNFS Polynomial

Polynomial

Degree: 7
Murphy: 2.82e-17
Skew: 1.39491
Selected: Best

n: 15998626902122785734478916025259371445087839066846331843763775490851714167735345664056701978718195915214824941034106110533345761829269920128282514453043980438376392031003178144844531369491923452362083612934632103158494908388545475693079542033948513
# 2^1217-1, difficulty: 366.65, skewness: 1.10
# cost: 2.24057e+22, est. time: 10669387.91 GHz days (not accurate yet!)
# Optimized skew: 1.39491 Murphy: 2.82e-17
skew: 1.39491
c7: 1
c0: -2
Y1: -1
Y0: 23945242826029513411849172299223580994042798784118784
type: snfs