Any number which has come to mean something to you is easily recalled
and may be helpful in remembering other numbers. As 1492, the date of
the discovery of America by Columbus. 57 immediately recalls "Heinz 57
varieties" and if you wish to remember 59 you can easily associate it
as being two more than the 57. 1775 means something to you, it conveys
a definite thought, but it is more likely that 1947 does not and will
be quickly forgotten.
If you have lived in a house with the number 1947 for a good while you
will remember it as easily as the number 1775.