route53: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/route53 - from package: python2-boto
/usr/bin/route53 - from package: python-boto

You may install the required package with command yum install {package}

Error in other languages:
route53: bevel nie gevind nie
route53: comandă negăsită
route53: comando não encontrado
route53: commande introuvable
route53: command not found
route53: käsku ei ole
route53: không tìm thấy lệnh
route53: komanda nerasta
route53: Kommando nicht gefunden.
route53: kommandot finns inte
route53: komut yok
route53: nie znaleziono polecenia
route53: níor aimsíodh an t-ordú
route53: no se encontró la orden
route53: no s'ha trobat l'ordre
route53: opdracht niet gevonden
route53: parancs nem található
route53: perintah tidak ditemukan
route53: príkaz nenájdený
route53: příkaz nenalezen
route53: команда не найдена
route53: командата не е открита
route53: 命令找不到
route53: コマンドが見つかりません