This number, as well as other personal details such as residential and email address, is available in the newly-developed [Account details] section when you go to your Menu 
and press Settings 
.
When using the web-based app, your account number is visible when you click on the top right corner of the screen, then on Settings - Account details.
An alternative, if you'd like to know your account number, would be referring to your monthly statements that we send to your email or by choosing to deposit funds to your account via Bank Wire.