Distribution of values of general Euler totient function

Debika Banerjee, Bittu Chahal, Sneha Chaubey +1

Let ${\Phi }_k(n)=|\{(x_1,x_2,\cdots ,x_k)\in {\left(\mathbb{Z}/n\mathbb{Z}\right)}^k;\gcd (x_1^2+x_2^2+\cdots +x_k^2,n)=1\}|$ be a general totient function introduced first by Cald…