primorial: 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 Debian possible default full paths are:

/usr/bin/primorial - from package: mathomatic-primes

You may install the required package with command apt-get install {package}

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