NTRU key size (confused) I'm evaluating the performance of NTRU; and I got confused. the key size is said to be smaller than RSA but larger than ECC.

Using both the reference implementation when I choose APR2011_439 setting from BC I've thought that 439 would represent the key size in bits. But when I store the public key in byte array its size if 604 bytes (PKCS1Encoding encoding). I'm very consufed. With APR2011_439 I can encrypt blocks of max 54 bytes in size so that would indeed be the key size. But why does the key stored in a byte array take a huge ammount of 604 bytes? It is the same with reference implementation.
Please explain I'm very short on time.
I've thourgh that 439 would represent the key size in bits.


No, NTRU doesn't measure things like that.  Instead, it's the number of elements in a ring.  In addition, with the current parameter sets, each ring element is a value between 0 and 2047 (11 bits), and the public key consists of one ring, and so it takes up $11 \times 439 = 4829$ bits, which compresses to 604 bytes.