13 (all 4 facts)
Fear of the number 13 is called triskaidekaphobia.submitted by: Dave on May 15th 2007 - 8:07
'Eleven plus two' is an anagram of 'twelve plus one'.
submitted by: Dave on June 11th 2007 - 6:04 pm
There are 13 Archimedian solids.
submitted by: Dave on Aug 25th 2008 - 10:46 pm
"A 13-Moon Calendar is the logical and natural way to count the 365-day year cycle. Instead of 12 months which are 28, 29, 30, or 31 days long, the year is instead measured into 13 months, each one an even 28 days," according to 13moon.com
submitted by: Dana Larson on Sep 3rd 2008 - 1:51 am