Solved 69.

python/e069.py

@@ -0,0 +1,62 @@
+
+
+def prime_factors(n):
+    f = []
+    while n % 2 == 0:
+        f.append(2)
+        n //= 2
+    d = 3
+    while d * d <= n:
+        while n % d == 0:
+            f.append(d)
+            n //= d
+        d += 2
+    if n != 1:
+        f.append(n)
+    return f
+
+assert(prime_factors(8) == [2, 2, 2])
+assert(prime_factors(2501232) == [2, 2, 2, 2, 3, 107, 487])
+
+
+def prime_factors_unique(n):
+    f = []
+    if n % 2 == 0:
+        f.append(2)
+    while n % 2 == 0:
+        n //= 2
+    d = 3
+    while d * d <= n:
+        if n % d == 0:
+            f.append(d)
+        while n % d == 0:
+            n //= d
+        d += 2
+    if n != 1:
+        f.append(n)
+    return f
+
+
+def prime_factors_count(n):
+    return len(prime_factors_unique(n))
+
+
+print(prime_factors_count(9699690))
+
+#factor_count_max = 0
+#n_max = 0
+#for n in range(1, 1000001):
+#    factor_count = prime_factors_count(n)
+#    if factor_count > factor_count_max:
+#        factor_count_max = factor_count
+#        n_max = n
+#print("factor count: {} n: {}".format(factor_count_max, n_max))
+
+
+def get_phi(n):
+    phi = n
+    for p in prime_factors_unique(n):
+        phi *= (1 - 1 / p)
+    return int(phi)
+
+print(get_phi(210412312))