When writing years in Spanish, it is the same as English. It is spelt:
mil novecientos noventa y ocho
FC Barcelona were the Spanish La Liga winners in 1998.
The Spanish Prisoner was released on 04/03/1998.
Barcelona
The winners of the Spanish La Liga Primera Division (LLPD) in 1998 were FC Barcelona.
Spanish Dance Troupe was created in 1998-09.
Sables-Spanish Rivers was created on 1998-01-01.
Spanish Fly - 1998 is rated/received certificates of: Australia:M Finland:K-15 (video rating) (2001) France:U USA:R
a dam broke spilling contaminated things into a river. this occurred April 25, 1998.
Guam!
fecha de nacimiento 13(trece) de julio de 1998
The cast of The Spanish American War - 1998 includes: Rod Paschall as Himself - Author and Historian Kathleen Sampson as Herself - Family of Admiral Sampson Fritz Weaver as Narrator Dana Wegner as Himself - Naval Historian
You would say "el número mil novecientos noventa y ocho".