The word according to the dictionary

Galician

**Galician numbers ^(edit)**
^{[a], [b], [c]} ← 500	600	700 →
	60^{[a], [b]}
Cardinal: seiscentos Ordinal (reintegrationist): seiscentésimo Ordinal: sexcentésimo Ordinal abbreviation: 600º Fractional (reintegrationist): seiscentésimo Fractional: sexcentésimo

seiscentos m (feminine seiscentas)

**Portuguese numbers ^(edit)**
← 500	600	700 →
	60
Cardinal: seiscentos Ordinal: sexcentésimo, seiscentésimo Ordinal abbreviation: 600.º Fractional: sexcentésimo, seiscentésimo, seiscentos avos
Portuguese Wikipedia article on 600

Inherited from Old Galician-Portuguese seiscentos, from Latin sexcentōs, accusative masculine plural of sexcentī, from sex (“six”) + centum (“hundred”).

(Brazil) IPA^(key): /sejˈsẽ.tus/
- (Rio de Janeiro) IPA^(key): /sejˈsẽ.tuʃ/
- (Southern Brazil) IPA^(key): /sejˈsẽ.tos/

(Portugal) IPA^(key): (careful pronunciation) /sɐjʃˈsẽ.tuʃ/, /sɐjˈʃẽ.tuʃ/
- (Northern Portugal) IPA^(key): (careful pronunciation) /sejʃˈsẽ.tuʃ/, /sejˈʃẽ.tuʃ/
- (Central Portugal) IPA^(key): (careful pronunciation) /sejʃˈsẽ.tuʃ/, /sejˈʃẽ.tuʃ/
- (Southern Portugal) IPA^(key): (careful pronunciation) /seʃˈsẽ.tuʃ/, /seˈʃẽ.tuʃ/

seiscentos m (feminine seiscentas)

seiscentos m (invariable)