#include<iostream>
#include<cstdio>
#define mod 998244353
using namespace std;
int read()
{
	char c=0;
	int sum=0;
	while (c<'0'||c>'9') c=getchar();
	while ('0'<=c&&c<='9') sum=sum*10+c-'0',c=getchar();
	return sum;
}
int fast_pow(int a,int b)
{
	int res=1,mul=a;
	while (b)
	{
		if (b&1) res=1ll*res*mul%mod;
		mul=1ll*mul*mul%mod,b>>=1;
	}
	return res;
}
void Adder(int &x,int d)
{
	x+=d;
	if (x>=mod) x-=mod;
	return;
}
int n,phin,k,res,ans,ans2;
int main()
{
	res=n=phin=read(),k=read();
	for (int i=2;i*i<=n;++i)
		if (res%i==0)
		{
			phin=phin/i*(i-1);
			while (res%i==0) res/=i;
		}
	if (res!=1) phin=phin/res*(res-1);
	ans=ans2=1;
	for (int i=1;i<=k-1;++i) ans=1ll*ans*(n-i)%mod,ans2=1ll*ans2*i%mod;
	printf("%lld\n",1ll*ans*fast_pow(ans2,mod-2)%mod*phin%mod);
	return 0;
}