3 syllables:
machinal, national, nationale, passional, rational

4 syllables:
binational, conational, cross-national, grand national, irrational, subnational, subrational, transnational, venational

5 syllables:
anti-national, antinational, internacional, international, internatonal, intranational, multinational, supernational, supranational, suprarational

6 syllables:
miscegenational

8 syllables:
marriott international, micro-star international, mondelez international, rotary international

9 syllables:
philip morris international, the family international

3 syllables:
traceable, capable, raisable, rateable, datable, changeable, saleable, great-uncle, salable, blamable, breakable, ratable, tamable, scalable, acapnial, acetal, actable, actinal, actual, addable, addible, admirable, affable, animal, astragal, battleful, canistel, cannibal, canticle, capital, cashable, casual, clavicle, fallible, fashionable, flammable, fractional, fragmental, graspable, laughable, madrigal, manacle, mandible, maximal, palatal, palpable, passable, placable, planetal, practical, radical, saxatile, tangible, taxable, trackable, tractable, vaginal, valuable

4 syllables:
erasable, replaceable, occasional, effaceable, insatiable, favorable, explainable, obtainable, unshakable, attainable, sustainable, debatable, exchangeable, unbreakable, assailable, reclaimable, untraceable, unsalable, incapable, available, persuadable, adaptable, attachable, block capital, collapsable, collapsible, compatible, contractable, dead animal, detachable, diagonal, draft animal, dutch capital, expandable, extractable, farm animal, free radical, french capital, grammatical, greek capital, hexagonal, impalpable, impassable, implacable, impractical, infallible, inflammable, infrangible, intangible, intractable, invaluable, moss animal, nontaxable, octagonal, pack animal, protractible, risk capital, sea animal, small capital, state capital, unflappable, unmatchable, unpassable, work animal

5 syllables:
unattainable, unexplainable, unassailable, irreplaceable, irreclaimable, interchangeable, ascertainable, unobtainable, unmistakable, unavailable, inescapable, belgian capital, british capital, cuban capital, danish capital, ethyl radical, finnish capital, german capital, gnawing animal, haitian capital, hemiacetal, incompatible, interactional, irish capital, marine animal, methyl radical, noncollapsable, noncollapsible, nonretractable, russian capital, semiannual, spanish capital, turkish capital, unadaptable, unattackable, understandable, ungrammatical, venture capital, vinyl radical, working capital

6 syllables:
anagrammatical, angolan capital, australian capital, austrian capital, brazilian capital, cyanide radical, diagrammatical, domestic animal, egyptian capital, fictional animal, hawaiian capital, honduran capital, indian capital, italian capital, jamaican capital, japanese capital, laotian capital, malaysian capital, methylene radical, mexican capital, national capital, provincial capital

7 syllables:
albanian capital, algerian capital, american capital, bulgarian capital, cambodian capital, canadian capital, hungarian capital, iranian capital, liberian capital, nicaraguan capital, nigerian capital, operating capital, predatory animal, salvadoran capital

8 syllables:
panamanian capital