The Number 221: Properties and Meanings
is a Centered Square Number
is a Centered 22-gonal Number
is the sum of the squares of the first 3
is the number of Hamiltonian Planar Graphs with 7
b, Baker Street, London, England is the address of Sherlock Holmes.
Aircraft: Boeing 221
Firearms: the .221
Remington Fireball pistol cartridge.
U.S. Route 221
The Year 221 AD
In the year 221
AD Liu Bei, Chinese warlord and descendant of the royal family of the Han Dynasty, proclaimed himself emperor. The Shu Han Kingdom was established.