A function f(r) is monotone of order p if its pth-derivative f(P)(r) fulfils that ( -1) p f(v) (r)>0. So, e.g. the monotonicity properties of order p = 0, 1, 2 describe the non-negativity (p = 0), the monotonic decreasing from the origin (p = 1) and the convexity (p = 2) of the function, respectively. Here, the monotonicity properties of the electron function g,,(r; ~)=(--t)" p(n)(r)r-~, ~>0, of the ground state of atomic systems are analysed both analytically and numerically. The symbol p(r) denotes the spherically averaged electron density. First of all, the condition which specifies, if exists, a value en; such that g,(r; c%) be monotone of order p is obtained. In particular, it is found that %1=max {rp'(r)/p(r)}, %2=max {q0(r)}, cql = max {rp"(r)/p'(r)} and cq2 = max {ql(r)}, where qo(r) and q~(r) are simple combinations of the first few derivatives of p(r). Secondly, numerical calculations of the first few values c% in a Hartree-Fock framework for all ground-state atoms with nuclear charge Z < 54 are performed. In doing so, the pioneering work of Weinstein, Politzer and Srebrenik about the monotonically decreasing behavior of p(r) is considerably extended. Also, it is found that Hydrogen and Helium are the only two atoms having the functions p(r), -p'(r) and p"(r) with the property of convexity. Thirdly, it is analytically shown that the charge function r ~ p(r) with e > [(1 + 4Z2/I) 1/2-1]/2,