2,520 is the smallest number that can be exactly divided by all the numbers 1 to 10.
At first sight, this number will be considered a normal number. But the strange thing is 2520 is able to be divided at even or odd number. Like 1=2520, 2=1260 , 3=840, 4=630, 5=504, 6=420, 7=360, 8=315, 9=280, and by 10=252, which is hard to find integers with the same characteristics.