import math
listOfPrimes = [2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,
                73,79,83,89,97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,
                179,181,191,193,197,199,211,223,227,229,233,239,241,251,257,263,269,271,277,281,
                283,293,307,311,313,317,331,337,347,349,353,359,367,373,379,383,389,397,401,409,
                419,421,431,433,439,443,449,457,461,463,467,479,487,491,499,503,509,521,523,541,
                547,557,563,569,571,577,587,593,599,601,607,613,617,619,631,641,643,647,653,659,
                661,673,677,683,691,701,709,719,727,733,739,743,751,757,761,769,773,787,797,809,
                811,821,823,827,829,839,853,857,859,863,877,881,883,887,907,911,919,929,937,941,
                947,953,967,971,977,983,991,997,1009,1013,1019,1021,1031,1033,1039,1049,1051,1061,1063,1069,
                1087,1091,1093,1097,1103,1109,1117,1123,1129,1151,1153,1163,1171,1181,1187,1193,1201,1213,1217,1223,
                1229,1231,1237,1249,1259,1277,1279,1283,1289,1291,1297,1301,1303,1307,1319,1321,1327,1361,1367,1373,
                1381,1399,1409,1423,1427,1429,1433,1439,1447,1451,1453,1459,1471,1481,1483,1487,1489,1493,1499,1511,
                1523,1531,1543,1549,1553,1559,1567,1571,1579,1583,1597,1601,1607,1609,1613,1619,1621,1627,1637,1657,
                1663,1667,1669,1693,1697,1699,1709,1721,1723,1733,1741,1747,1753,1759,1777,1783,1787,1789,1801,1811,
                1823,1831,1847,1861,1867,1871,1873,1877,1879,1889,1901,1907,1913,1931,1933,1949,1951,1973,1979,1987,
                1993,1997,1999,2003,2011,2017,2027,2029,2039,2053,2063,2069,2081,2083,2087,2089,2099,2111,2113,2129,
                2131,2137,2141,2143,2153,2161,2179,2203,2207,2213,2221,2237,2239,2243,2251,2267,2269,2273,2281,2287,
                2293,2297,2309,2311,2333,2339,2341,2347,2351,2357,2371,2377,2381,2383,2389,2393,2399,2411,2417,2423,
                2437,2441,2447,2459,2467,2473,2477,2503,2521,2531,2539,2543,2549,2551,2557,2579,2591,2593,2609,2617,
                2621,2633,2647,2657,2659,2663,2671,2677,2683,2687,2689,2693,2699,2707,2711,2713,2719,2729,2731,2741,
                2749,2753,2767,2777,2789,2791,2797,2801,2803,2819,2833,2837,2843,2851,2857,2861,2879,2887,2897,2903,
                2909,2917,2927,2939,2953,2957,2963,2969,2971,2999,3001,3011,3019,3023,3037,3041,3049,3061,3067,3079,
                3083,3089,3109,3119,3121,3137,3163,3167,3169,3181,3187,3191,3203,3209,3217,3221,3229,3251,3253,3257,
                3259,3271,3299,3301,3307,3313,3319,3323,3329,3331,3343,3347,3359,3361,3371,3373,3389,3391,3407,3413,
                3433,3449,3457,3461,3463,3467,3469,3491,3499,3511,3517,3527,3529,3533,3539,3541,3547,3557,3559,3571,
                ]
listOfNewPrime = []

def getNextPrime():
    global listOfNewPrime
    cur = 0
    while cur < len(listOfPrimes):
        yield listOfPrimes[cur]
        cur += 1

def BinarySearch(A, value):
    low = 0
    high = len(A) - 1
    while low < high:
        mid = (low + high) / 2
        if A[mid] > value:
            high = mid - 1
        elif A[mid] < value:
            low = mid + 1
        else:
            return True

    
    return False


def isPrime(num):
    if num in listOfPrimes:#BinarySearch(listOfPrimes, num):
        return True
    if num < listOfPrimes[-1]:
        return False
    
    checkUpTo = int(math.sqrt(num))
    for prime in getNextPrime():
        if prime > checkUpTo:
            return True
        if num%prime == 0:
            return False
    return True

def readNextWord():
    data = []
    cur = 0
    while True:
        if len(data) == cur:
            st = raw_input()
            data = st.split()
            cur = 0
        yield data[cur]
        cur += 1

def getNextInt(reader):
    return int(float(next(reader)))

def isPrimeString(string):
    letterCount = [0]*26
    
    for l in string:
        letterCount[ord(l) - ord('a')] += 1
    nonZero = 0
    for count in letterCount:
        if count > 0:
            nonZero += 1
    if nonZero <= 0 or isPrime(nonZero) == False:
        return False
    
    for count in letterCount:
        if count == 0:
            continue
        if count == 1:
            return False
        if isPrime(count) == False:
            return False
    return True

def main():
    #add you code here
    reader = readNextWord()
    T = getNextInt(reader)
    while T:
        T -= 1
        string = next(reader)
        if isPrimeString(string):
            print "YES"
        else:
            print "NO"

if __name__ == "__main__":
    #isPrimeString("aabbccdd")
    main()