2+(odd)

2^1285+1

Open composite · C292

NFS Planning

GNFS Murphy estimate: 2.59e-20
SNFS Murphy score: 4.89e-16
Preferred method: SNFS
SNFS possible: Yes
SNFS degree: 8
SNFS skew: 0.78605

Identifiers

Target expression: 2^1285+1
Target link: FactorDB page
Target ID: 1000000000012151309
Target changed: -
Parent query: Same as target
Parent ID: -
Cofactor token: C292
Imported: Jun 03, 2026, 04:29 PM UTC

Raw pmain126 Factorization

(1,5,257) 1441771.67548618131. C292

SNFS Polynomial

Polynomial

Degree: 8
Murphy: 4.89e-16
Skew: 0.78605
Selected: Best

n: 2684912289008022410489846388952607931642620126042984699011175827736129333206715362860833920761181901437555019243093426145116453375105457369188239756488137147476551595856078478023063651543067273760118385963083036257822315431732679634754991424517554602952618797430701727840327409068519099949011
# 2^1285+1, difficulty: 309.46, skewness: 0.71
# cost: 5.83448e+20, est. time: 277832.17 GHz days (not accurate yet!)
# Optimized skew: 0.78605 Murphy: 4.89e-16
skew: 0.78605
c8: 16
c6: -8
c4: 4
c2: -2
c0: 1
Y1: -1
Y0: 340282366920938463463374607431768211456
type: snfs