The number 536,256 can be evenly divided by 1 2 3 4 6 7 8 9 12 14 16 18 19 21 24 28 32 36 38 42 48 49 56 57 63 64 72 76 84 96 98 112 114 126 133 144 147 152 168 171 192 196 224 228 252 266 288 294 304 336 342 392 399 441 448 456 504 532 576 588 608 672 684 784 798 882 912 931 1,008 1,064 1,176 1,197 1,216 1,344 1,368 1,568 1,596 1,764 1,824 1,862 2,016 2,128 2,352 2,394 2,736 2,793 3,136 3,192 3,528 3,648 3,724 4,032 4,256 4,704 4,788 5,472 5,586 6,384 7,056 7,448 8,379 8,512 9,408 9,576 10,944 11,172 12,768 14,112 14,896 16,758 19,152 22,344 25,536 28,224 29,792 33,516 38,304 44,688 59,584 67,032 76,608 89,376 134,064 178,752 268,128 and 536,256, with no remainder.
Since 536,256 cannot be divided by just 1 and 536,256, it is a composite number.