include <bits/stdc++.h>

using namespace std;
int prime (int n){
if (n<2) return 0;
for (int i=2;i<=sqrt(n);++i){
if (n%i==0) return 0;
}
return 1;
}
int main(){
int n,q,d=0,a[26]={};
string s,st;
freopen("prime_string.inp","r",stdin);
cin>>q;
for (int k=0;k<q;k++){ st=""; d=0; cin>>s;
n=s.length();
int tam=0,j=0;
for (int i=0;i<n;i++){
a[int(s[i])-97]++;
}
for (int i=0;i<26;i++){
if(a[i]==1)
d++;
}
if (prime(d)) cout<<"YES";
else
cout<<"NO";
cout<<endl;
}
return 0;}