Yes, 123456789 is a multiple of 9
123456789 + 123456789 = 246913578
Yes, 123456789 is a multiple of 3. To find out if it's a multiple of 3, you add the digits. In this case you would add 1+2+3+4+5+6+7+8+9=45. Now you take that 45 and divide by 3. If there is no remainder it is a multiple but if there is a remainder it is not a multiple. So in this case 45/3=15 with no remainder.
Oh, isn't that a lovely question! Divisibility by such a large number like 123456789 is quite rare, but every number is special in its own way. It may take some time to find numbers that can be divided by 123456789, but I believe with a patient heart and a curious mind, you can uncover the beauty of these unique numbers. Just remember, every number has its place in the mathematical landscape, just like every tree has its place in a beautiful forest.
the answer is 15241578750190521
you get cheese
543234567890-123456789 = 543111111101
1
324536
123456789 + 36853168 = 160309957
123456789 +987654321 =1111111110
123456789-987654321 = -864197532