求助，卡在66分，哪里还可以优化？

import random
import time
import math

def leap_number(x):
    number_size=0
    number_judge=0
    temp=x
    while True:
        number_size+=1
        temp//=10
        if temp==0:
            break
    if x>=5 and x<=9:
        return x
    else:
        for i in range(number_size//2):
            if x//math.pow(10,i)%10==x//math.pow(10,number_size-i-1)%10:
                number_judge+=0
            else:
                return -1
                break
        if number_judge==0:
            return x
        else:
            return -1

def prime_number(x):
    if x%2==0:
        return -1
    if x>=5 :
        for i in range(2,int(math.sqrt(x))+1,1):
            if x%i==0:
                return -1
                break
        return x

a,b=map(int,input().split())
for i in range(a,b+1,2):
    if i%2!=0 and leap_number(i)==i and prime_number(i)==i:
        print(i)