Nope. That's the maximum length of a TXT record string. TXT record strings with the same owner name get concatenated together. The maximum for a TXT record is 65,280 octets (which may or may not translate into characters depending on encoding).
Also, you probably want to think about the implications of caching and TTL.
finger nochan.net
"bing bing bong."
"Catching up on HN"label IN TXT "foo " IN TXT "bar " IN TXT "baz"
You can have any number of TXT RRs with a label, allowing up to 65,280 bytes. However, resolvers can reorder those 3 TXT RRs.
If you put the text strings in quotes in a single TXT RR, e.g.:
label IN TXT "foo " "bar " "baz"
You'll get "foo bar baz" and each of the strings can be up to 255 bytes. I think (but I'm too lazy to verify) that the maximum length of a concatenated string is implementation dependent.
for i in $(seq 100);do echo -en '0';done
0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
test 69s in txt "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"
nsd-checkzone nochan.net ./nochan.net.zone
zone nochan.net is ok
nsd-control reload nochan.net
ok
# from my laptop
dig -t txt +short test.nochan.net
"0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"