/*
TASK: mink
LANG: C++
*/
#include <cstdio>

long long mink, key, N, p1, p2;

void go ( int k, int l ) {

	if ( k && p2 == N * p1 ) {
		mink = k;
		key = 1;
		printf ( "%d\n", k );
		return;
		}

	for ( int a=l; a<2000; ++a ) {
		p1 *= a; p2 *= ( a+1 );
		if ( !key && k < mink && p2 <= N * p1 ) go ( k+1, a );
		p1 /= a; p2 /= ( a+1 );
		}
	
}

int main (void) {

	scanf ( "%lld", &N );

	mink = 14, key = 0;
	p1 = p2 = 1;
	go ( 0, 1 );
	
}
