sprop: command not found

Have You tried accessing the binary with the full path?

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/sprop - from package: suckless-tools

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