Also, you don't need to check if the same digits from different joins are not equal (eg. if checked a.num<>b.num in one "join" you don't need to check it again in other "joins"). Therefore all JOINs can be rewritten using "incremented" NOT IN:

with a(num) as

(select 1 union select 2 union select 5 union select 7 union select 8 union select 9)

,b(num1,num2) as

(

select

convert(bigint, '4' + convert(varchar,a.num) + convert(varchar,b.num) + convert(varchar,c.num) + '6')

,convert(bigint, convert(varchar,d.num) + convert(varchar,e.num) + convert(varchar,f.num) + '3')

from

a

join a as b on a.num <> b.num

join a as c on c.num NOT IN (a.num, b.num)

join a as d on d.num NOT IN (a.num, b.num, c.num)

join a as e on e.num NOT IN (a.num, b.num, c.num, d.num)

join a as f on f.num NOT IN (a.num, b.num, c.num, d.num, e.num)

)

select distinct *, num1-num2 from b

where num1-num2 = 33333

order by 1,2