We have the following code

# ENCRYPT.py

from sympy import isprime, prime

flag = '<REDACTED>'

def Ord(flag):
    x0r([ord(i) for i in flag])
    
def x0r(listt):
    ff = []
    for i in listt:
        if isprime(i) == True:
            ff.append(prime(i) ^ 0x1337)
        else:
            ff.append(i ^ 0x1337)
    b1n(ff)

def b1n(listt):
    ff = []
    for i in listt:
        ff.append(int(bin(i)[2:]))
    print(ff)
    
if __name__ == "__main__":
    Ord(flag)

'''
 OUTPUT :
[1001100000110, 1001100000100, 1001100000100, 1001100000000, 1001101100010, 1001101100111, 1001101001100, 1001101001111, 1001100000111, 1001101000101, 1001101101000, 1001100000011, 1001101011001, 1001101110011, 1001101101000, 1001101110101, 1001101011110, 1001101011001, 1001100000011, 1001011001010, 1001101100101, 1001101001110, 1001101101000, 1001101110010, 1001101011001, 1001001111100, 1001100000111, 1001101010011, 1001100000100, 1001101000101, 1001101101000, 1001100000011, 1001101000101, 1001100000100, 1001101101000, 1001101000011, 1001101111111, 1001100000100, 1001101101000, 1001101100000, 1001100000100, 1001100000011, 1000101111100, 1001100000100, 1001111000110, 1001101000011, 1001101101000, 1001100001111, 1001100000111, 1001100000000, 1001100001110, 1001100000111, 1001100000000, 1001111000110, 1001100000001, 1001101001010]
'''

We can easily decode the output by reversing the process.

from sympy import isprime, prime, sieve

# Transforms base2 to base10.
def unb1n(bin):
    dec = []
    for i in bin:
        b = str(i)
        #print(b, int(b,2))
        dec.append(int(b,2))
    return unx0r(dec)


def unx0r(lista):
    un = []
    for i in lista:
        x = i ^ 0x1337
        if isprime(x):
            # if the number we get is prime it means we need
            #to get its index in the sieve to get the original number 
            un.append(sieve.search(x)[0])
        else:
            un.append(x)
    return to_char(un)

def to_char(lista):
    return "".join(chr(c) for c in lista)

bin = [1001100000110, 1001100000100, 1001100000100, 1001100000000, 1001101100010, 1001101100111, 1001101001100, 1001101001111, 1001100000111, 1001101000101, 1001101101000, 1001100000011, 1001101011001, 1001101110011, 1001101101000, 1001101110101, 1001101011110, 1001101011001, 1001100000011, 1001011001010, 1001101100101, 1001101001110, 1001101101000, 1001101110010, 1001101011001, 1001001111100, 1001100000111, 1001101010011, 1001100000100, 1001101000101, 1001101101000, 1001100000011, 1001101000101, 1001100000100, 1001101101000, 1001101000011, 1001101111111, 1001100000100, 1001101101000, 1001101100000, 1001100000100, 1001100000011, 1000101111100, 1001100000100, 1001111000110, 1001101000011, 1001101101000, 1001100001111, 1001100000111, 1001100000000, 1001100001110, 1001100000111, 1001100000000, 1001111000110, 1001100000001, 1001101001010]
print(unb1n(bin))

❯ python solve.py
1337UP{x0r_4nD_Bin4aRy_EnC0d3r_4r3_tH3_W34k35t_80790756}