February is the only month that has a number of days divisible by 4 (to produce a integer).
That's because February has 28 days, and you can divide 28 by 4 to give you 7.
All the other months have 30 or 31, days, and 30 / 4 doesn't give you a whole number, and neither does 31.
To answer the second part of the question, no. During a leap year, February has 29 days. You can't divide 29 by 4 to give a whole number, hence it is then not true.
