The numbers 3 and 7 both are considered "perfect numbers" under Hebrew tradition.
According to the American publication, the Orthodox Study Bible, 777 represents the threefold perfection of the Trinity. The number 777, as triple 7, can be contrasted against triple 6, for the Number of the Beast as 666 (rather than variant 616).
In other traditions and teachings, seven is seen as the perfect number that holds creation and the universe together. Religious or mythological cosmology refers to seven heavens, ancient Indian spiritual texts detail seven chakras and esoteric teachings describe seven planes of creation.
777 Tower is an office building situated in the US and it was built in 1991.
Gambling and luck
777 is used on most slot machines in the United States to identify a jackpot. As it is considered a lucky number, banknotes with a serial number containing 777 tend to be valued by collectors and numismatists. The US Mint and the Bureau of Engraving and Printing sells uncirculated 777 $1 bills for this reason.