#include<stdio.h>

int main(void)
{
	unsigned long long int a, b, c, i, j;
	int ret = 0;
	
	scanf("%lld", &a);

	for (i = 2; i <= a; i++) {
		b = 0;
		c = 1;
		for (j = 2; j < i / 2; j++) {
			if (i % j == 0) {
				b = 1;
				break;
			}
		}

		if (b != 1) {

			while (1) {
				for (j = 0; j < c; j++) {
					if (a % i != 0) {
						b = 1;
						break;
					}
					a = a / i;
				}

				if (b == 1) {
					break;
				}

				ret++;
				c++;
			}
		}
	}

	printf("%d", ret);

	return 0;
}