29 - it was a leap-year
1964 was a leap year, so 29 days.
13
February 1930, had 28 days.
There was 29 days in February of 1836.
February 2010 had 28 days.
February 2010 has 28 days.
February 2000 had 29 days.
February 1986 had 28 days.
In 2002, February had 28 days.
February 1971, had 28 days.
There are 28 days in February 2011.
February 1990 had 28 days.