n = int(input())
m = 60000
a = [(i ** 2 * (i + 1) ** 2) // 4 for i in range(m)]
i = j = 0
ans = []
while i < m:
    while j < m and a[j] - a[i] < n:
        j += 1
    if j == m:
        break
    if a[j] - a[i] == n:
        ans.append((i + 1, j))
    i += 1

print(len(ans))
for ai in ans:
    print(*ai)