On an asymptotic formula for the Niven numbers
The positive integer n is called a Niven number, if n is divisible by its digital sum s(n). For fixed \(k\in {\mathbb{N}}\) the authors deduce the asymptotic formula \(N_ k(x)\sim c_ k \log^ k x\) \((x\to \infty)\), where \(N_ k(x):=\#\{n\in {\mathbb{N}}:\) \(n\leq x,\quad s(n)=k\) and \(s(n)| n\}.\)
scientific article; zbMATH DE number 3931101