Cryptography Challenge

I have been messing around with cryptography (for recreational use) and I have created my own function that encrypts things for me. Now, with that being said, I freely admit that I am by no means an expert on cryptography and I know that rule 101 of cryptography is to not do it yourself. However, I am genuinely interested if my encryption function is secure. So, although I am not entirely sure if this is the right forum to post it on, I wanted to see if anyone can crack my encrypted message (attached below). For those who like a challenge, I think this will be a fun one (and I get to learn all the holes in my encryption logic if someone figures out the message). For those who want to participate in this challenge, simply respond with what you think the decrypted message is and I will verify whether you are correct or not.

Encrypted Message: 37126281017225427352134331913330220051479104178502548903187948952952485342724203650753089

Good Luck!

This isn't really how it works, on multiple levels. Here is a ciphertext that I encrypted using Vigenère: GJRYWP. Can you decrypt it ? Probably not, because depending on the key you try, you can obtain HELPME, BANANA or every other 6-letters possibility. It's the same here.

Now you could "fix" this issue by giving more ciphertexts, or maybe a plaintext/ciphertext couple, but as it will inevitably be cracked, the best option is probably to just post your encryption function and ask what's weak or wrong in it, to save everyone's time. After all, a very important saying in cryptography is that the only thing that should be secret is the key, and the fact that the whole algorithm becomes known must not affect its security.