duration
length
durability
enduringness
immortality
imperishability
imperishableness
imperishingness
lastingness
perdurability
perpetuity
sempiternity
strength
closeness
cogency
coherence
cohesion
compactness
completeness
comprehensiveness
conclusiveness
continuity
definiteness
homogeneity
impenetrability
inutility
permanence
perspicuity
pleasantness
predictability
singleness
soundness
steadiness
strictness
thoroughness
totality
uniformity
wholeness