807,875
The 1956 Topps baseball card set includes 340 horizontal cards that measure 3¾" by 2 5/8". The 1955 Topps baseball cards are the first to feature team cards as well as the two league presidents. The high number series (181-340) is slightly more difficult and expensive to collect.
The key rookie cards include #292 Luis Aparicio.
2010 Who's Who in Baseball