Problem:
Score : 400 points

Problem Statement

Given is a positive integer N. Consider repeatedly applying the operation below on N:

First, choose a positive integer z satisfying all of the conditions below:

z can be represented as z=p^e, where p is a prime number and e is a positive integer;

z divides N;

z is different from all integers chosen in previous operations.

Then, replace N with N/z.

Find the maximum number of times the operation can be applied.

Constraints

All values in input are integers.

1 \leq N \leq 10^{12}

Input

Input is given from Standard Input in the following format:

N

Output

Print the maximum number of times the operation can be applied.

Sample Input 1

24

Sample Output 1

3

We can apply the operation three times by, for example, making the following choices:

Choose z=2 (=2^1). (Now we have N=12.)

Choose z=3 (=3^1). (Now we have N=4.)

Choose z=4 (=2^2). (Now we have N=1.)

Sample Input 2

1

Sample Output 2

0

We cannot apply the operation at all.

Sample Input 3

64

Sample Output 3

3

We can apply the operation three times by, for example, making the following choices:

Choose z=2 (=2^1). (Now we have N=32.)

Choose z=4 (=2^2). (Now we have N=8.)

Choose z=8 (=2^3). (Now we have N=1.)

Sample Input 4

1000000007

Sample Output 4

1

We can apply the operation once by, for example, making the following choice:

z=1000000007 (=1000000007^1). (Now we have N=1.)

Sample Input 5

997764507000

Sample Output 5

7

Solution in PyPy3 (7.3.0) (judge verdict: Runtime Error)

import sys
input = sys.stdin.readline

"""
z = p^e where p is a prime number and e = positive int
z divides N
"""

def get_primes(up_to=1000):
    primes = []

    A = [True] * (up_to + 2)

    for i in range(2, int(up_to**0.5)+1):
        if A[i]:
            j = i*2
            while j < up_to:
                A[j] = False
                j += i
    
    i = 2

    while i < up_to:
        if A[i]:
            primes.append(i)
        i += 1

    return primes

from math import sqrt

n = int(input())
used = set()
primes = get_primes(int(sqrt(n))+2)
ze = []
for z in primes:
    i = 1
    zval = z**i
    while zval <= n:
        if not(zval in used):
            ze.append(zval)
            used.add(zval)
        i += 1
        zval = z**i

ze.sort()

count = 0

for z in ze:
    if z > n:
        break

    if n % z == 0:
        count += 1
        n //= z

def is_prime(n):
    if n < 2:
        return False
    elif n == 2 or  n == 3:
        return True

    for i in range(2, int(sqrt(n))+2):
        if n % i == 0:
            return False
    return True

#print(primes)
if not ze:
    print(0)
if n > ze[-1] and is_prime(n):
    print(count +1)
else:
    print(count)