How can I convert a date from bigint to timestamp?

There is a DB on Postgresql in one of the tables there are records of date and time in a strange format, examples:
Field types - bigint, we need to timestamp
1450064047334124
1450075512512631

How to bring them into a readable form in the format 'YYYY-MM-DD HH-MM-SS' ?

Tried:

receipt_t1 = '1450064047334124'
TO_CHAR(TO_TIMESTAMP(receipt_t1 / 1000), 'DD/MM/YYYY HH24:MI:SS') get "14/09/47920 03:42:14"

receipt_t1 = '1450064047334124'
TO_CHAR(TO_TIMESTAMP(receipt_t1 / 86400), 'DD/MM/YYYY HH24:MI:SS') get "02/11/2501 20:44:55"

know exactly for sure what the values should be approximately equal 2015-12-12 date
July 9th 19 at 13:41
1 answer
July 9th 19 at 13:43
Solution
So try
select to_timestamp(1450075512512631/1e6);

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