2215 => 400 x 5 + 200 + 15 => 400 years has zero' odd days.
=> 200 years has three odd days.
=> 15 years 3 leap and 12 ordinary years. No.of odd days=0+3+6+12 =21
On dividing 21 by 7 remainder zero
Jan 1 2215 is Sunday
January=>30, February=> 28, March =>31, April =>30, May =>31, June =>8 30+28+31+30+31+8 = 158
On dividing 158 by 7 remainder 4
Sunday+4 => Thursday
