Shouldn't the select below return "5300" for the value?

field1 = "CAMINO LOS REALES LOT#5300"

select substr(field1,AT('#',field1)+ 1) from TABLE1 into cursor query

All I am getting as a returned result is the first character of 5. I tried doing query below to force substr to return 10 characters after the number that the AT() function returns, but again all I get is the first character. I've tried several variations of this simple SQL but can't get it to return every thing to the right of the "#". If I use the command window and just use -> substr(field1,AT('#',field1)+ 1)
the returned value is correct, but for some reason SQL doesn't work with this construct. Any help greatly appreciated.

Thanks,

John