  In this paper, we look to analyse the spiral features of grand-design,
multiarmed, and flocculent spiral galaxies using deep optical imaging from DESI
Legacy Imaging Surveys. We explore the resulting distributions of various
characteristics of spiral structure beyond the optical radius, such as the
distributions of azimuthal angle, the extent of spiral arms, and of the spiral
arm widths for the aforementioned galaxy classes. We also compare the measured
properties for isolated galaxies and galaxies in groups and clusters. We find
that, on average, compared to multiarmed and flocculent spiral galaxies, the
spiral arms of grand-design galaxies exhibit slightly larger azimuthal angles,
greater extent, and larger widths in the periphery of the galaxy. Furthermore,
on average, isolated galaxies tend to have slightly smaller widths of outer
spiral arms compared to galaxies in tight environments, which is likely related
to the tidally-induced mechanism for generating wider outer spiral arms. We
also report that breaks of the disc surface brightness profiles are often
related to the truncation of spiral arms in galaxies.
