Answer: 476

Solution:

Every number is congruent to its digit sum modulo $9,$ so $m = 17n$ must satisfy $17n \equiv 17 \pmod 9,$ that is $8n \equiv 8 \pmod 9,$ which gives $n \equiv 1 \pmod 9.$

Checking the candidates in increasing order: $n = 1, 10, 19$ give $17,$ $170,$ $323,$ with digit sums $8$ each, but $n = 28$ gives $17 \cdot 28 = 476$ with digit sum $4 + 7 + 6 = 17.$ So $m = 476.$