I don't believe initially there was a limit but devs changed it to 5460 sats to prevent spamming.
edit: Wow! That's almost two bucks US now!!
edit2: Nice hat by the way.
Surprisingly blockchain.com allows to send 546 satoshis which is the minimum possible value and posted on their official site itself by the support few days back.
What is the minimum amount I can send?
The minimum amount of bitcoin you can send in a transaction is 546 Satoshis, which is equivalent to .00000546 BTC.
Creator of the hat getting amazed at it.
Depends on the input/output types. It's 3 times the minimum fee (1 sat per byte) so for p2pkh TX it would be 546 sat and for native segwit it can be as low as ~300 sat IIRC.
I remembered it correctly, exactly sent 300sats from native segwit to native segwit with fee of 6sat/byte which placed at 0.5 mb from mempool.And tried the same amount 3 times then lost my patience and send few dollars.