Looking at the kernel that comes with it, it is using Ubuntu-Core kernel 4.4.0-1030 https://launchpad.net/ubuntu/+source/linux-raspi2/4.4.0-1030.37 which is showing that it's architecture is armhf in which it looks to be 32 bit.
From this answer https://unix.stackexchange.com/a/125314/111521 :
ARM processors have a completely different instruction set. You cannot
install an x86 or x86-64 package on an ARM system. You need a package
for ARM, for the correct instruction set, and more generally for the
correct ABI. There are no major 64-bit distributions for 64-bit ARM
processors yet, because the ARMv8 architecture revision which
introduces a 64-bit instruction set is still very new and not commonly
available. There are however multiple 32-bit ABIs, which assume the
existence of different processor features and use different versions
of the argument-passing convention. The main ARM ABIs used on Linux
are:
armel, based on the ARM EABI version 2 (known as “ARM EABI” or “EABI”
for short), in its little-endian incarnation;
armhf, which is a
variant of armel that takes advantage of some features of newer ARM
CPUs, in particular hardware floating-point support.
Also look here for more information: https://wiki.debian.org/ArmHardFloatPort
This shows 32 bit as well: https://wiki.debian.org/ArmPorts
Hope this helps!
