2+(odd)

2^1387+1

Open composite · C334

NFS Planning

GNFS Murphy estimate: 9.48e-23
SNFS Murphy score: 5.63e-19
Preferred method: SNFS
SNFS possible: Yes
SNFS degree: 7
SNFS skew: 0.86501

Identifiers

Target expression: 2^1387+1
Target link: FactorDB page
Target ID: 1000000000012151411
Target changed: -
Parent query: Same as target
Parent ID: -
Cofactor token: C334
Imported: Jun 03, 2026, 04:29 PM UTC

Raw pmain126 Factorization

(1,19,73) 14668142459117517676637603.31468486590867461800836388667587.C334

SNFS Polynomial

Polynomial

Degree: 7
Murphy: 5.63e-19
Skew: 0.86501
Selected: Best

n: 4433164379601628148285948054686111092441548347109165892978872806840535152115595190669386156284448550863174744210052140052269756915718212498938848704290814811145275410941003776301196668686010953058988416409392745023850387708594108897339149598080129165504647342305075987127832790031317655135193749354916640299987602278751181227180464971
# 2^1387+1, difficulty: 417.53, skewness: 1.10
# cost: 4.35227e+23, est. time: 207251044.77 GHz days (not accurate yet!)
# Optimized skew: 0.86501 Murphy: 5.63e-19
skew: 0.86501
c7: 1
c0: 2
Y1: -401734511064747568885490523085290650630550748445698208825344
Y0: 1
type: snfs