I would say so.
5 number 1's from one album
Getting a star on the walk of fame
She has her own movie( one of 5 most succesfull concert documentaries of all time)
Many awards such as mutiple VMa's,Ema's,Ama's,People's Choice,Trevor Project award for Hero of the year,Billboard's woman of the year and had 9 grammy nominations including album of the year nominee.
She's been on the cover of almost every magazine out there including 2 Rolling Stone covers,Vogue,Maxim,2 Elle covers,Fhm,Vanity Fair,2 Cosmopolitan covers and many more
She's one of the most liked people on facebook with over 54 million likes and the 3rd( soon to be 2nd) most followed person on twitter with over 34 million followers.Every year she's one of the most searched celebrities on google and one of the sexiest women on the world by magazines like Fhm,MAxim and Mean's Health
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these are just some of her records
◘ Most conseccutive weeks in the top 10 of the Hot 100.
◘ Only artist to have 4 #1 adult pop songs from one album.
◘ Only artist to have 5 #1s on the Mainstream Top 40 (Pop songs) from one album.
◘ Only female artist have 5 #1s on the Hot 100 from one album.
◘ Only one of two artists to have 5 #1s on the Hot 100 from one album.
◘ Only artist to have 5 songs spend more than one week at #1 on the Hot 100 from one album.
◘ Only artist to have 5 songs with writing credits go to #1 from one album.
◘ Artist with the most songs that sold over 4 million in the US.
◘ Artist with the most songs that sold over 3 million in the US.
◘ Artist with the most #1s on the Canadian Hot 100.
◘ Broke the spin record with California Gurls, broke it again with ET, and broke it further with Last Friday Night (in fact 5 of the top 6 highest spins belongs to Katy Perry)
◘ The only artist to have four different songs to be nomminated at the VMAs.
◘ Tied Beyonce for most #1s from one album on the Dance Club chart (6)
◘ The first and so far only artist to have five #1s on the Hot 100 this decade.
◘ ET and California Gurls sold over 300,000 digital copies in a week four times, two of only four songs in history to do so. Katy is the only artist to do that with two songs.
◘ Within seven weeks California Gurls sold over two million downloads, which is the second fastest pace to do so in
digital history, fastest for a female artist.
◘ Only artist to have 3 songs go to #1 on the Hot 100 in one calendar year for two consecutive years.
◘ Only artist in digital history to top 300K in weekly sales with four different songs.
◘ Teenage Dream"set the record for most added song in a week with 64 new stations and 14.9 million plays
She's a sex symbol,fashion icon,one of the leading pop stars in the game and one of the most famous people on the world. And if she's not a legend yet she will be with her 3rd era for sure.
how can u not call her a legend? 
