Mass of a black hole that tears you apart at its horizon

(* clear units *)
Clear[c,G,Msun,gee];

(* Schwarzschild radius rs in terms of mass M *)
rs=((2G M)/(c^2))

(* tidal force Δg between points Δr apart at the horizon = Δg = ((\[DifferentialD]g)/(\[DifferentialD]r))Δr = ((2GM)/(r^3))Δr where g = (G/(r^2)) is the gravitation acceleration *)
(* mass of black hole which has tidal force of 1 gee per meter at the horizon *)
Mgee=M/.Solve[((2G M)/(rs^3))==gee,M][[2]]

(* density of black hole which has tidal force of 1 gee per meter at the horizon *)
((3M)/(4π (rs^3)))/.M->Mgee

(* speed of light c in m/s (exact) *)
c=299792458;
(* Newton's G in (m^3)(kg^(-1))(s^(-2)) *)
G=6.67384 (10^(-11));
(* solar mass in kg *)
Msun=1.9891 (10^30);
(* Earth gee in m (s^(-2)) (exact) *)
gee=9.80665;

(* mass of black hole which has tidal force of 1 gee per meter at the horizon, in solar masses *)
(Mgee/Msun)

(* density of black hole which has tidal force of 1 gee per meter at the horizon, in kg/(m^3) *)
((3M)/(4π (rs^3)))/.M->Mgee