nBit to leading zeros in Block Hash I am trying to understand how can I check if my Block Hash satisfies or not the nBits.
For example, for block 506679 (https://blockchain.info/block-index/506679):

nBits: 404454260
Block Hash: 000000000000000015A8D88216918C8DE090268A5E7F53FEEF72CD111F7F27FF

How can I double check that this Block Hash satisfies the nBits?
PS: I have already read the What does the nBits value represent? but I could not find the answer.
The bits value you have written is in decimal, in hex it is 0x181b7b74

We split this into the exponent and mantissa as shown in this answer: https://bitcoin.stackexchange.com/a/61951/51948

0x18 in decimal is 24, so we calculate the target to be:
0x1b7b74000000000000000000000000000000000000000000

Now as the target takes up 24 bytes, out of the total 32 bytes for a block hash, the remaining 8 bytes must be 0's in order for the hash to be less than the target  (as well as the rest of the number being less than, of course). Usually leading 0's are omitted for readibility, but 8 zero bytes is written as 16 zero characters in hexadecimal, which is why the hash must have at least 16 leading zeros - which it does.