def fast(n):
	ans = 0
	x = 1

	while min(n, x*x) != n:
		ans += x * (x-1) * (x+1) // 6
		x += 1

	lb = x
	ub = n + 1

	k = 1
	while k <= n:
		tub = (n-1) // k
		tlb = x
		if tlb > tub:
			break
		vlb = k * tub + 1
		vub = min(n + 1, k * (tub + 1) + 1)
		ans += (vub - vlb) * (vub - vlb + 1) // 2
		tub -= 1
		if tlb <= tub:
			ans += (tub - tlb + 1) * k * (k+1) // 2
		k += 1

	for x in range(1, n+1):
		ub = n
		lb = min(n, x*x)
		if lb == ub: break
		ubv = ub//x
		ubr = ub%x
		lbv = lb//x
		lbr = lb%x
		ans += x * (x-1) // 2 * ubv + ubr * (ubr+1) // 2
		ans -= x * (x-1) // 2 * lbv + lbr * (lbr+1) // 2
	
	return ans

n = int(input())
print(fast(n) % 998244353)