> Both Chicken and Guile return (exact? 123#) => #f so that number is
> probably not distinguishable from the float 123.0.

I meant 1230.0.

Chicken:

(=    123# 1230.0)  ; => #t
(eqv? 123# 1230.0)  ; => #t
(eq?  123# 1230.0)  ; => #f !!

Guile:

(=    123# 1230.0)  ; => #t
(eqv? 123# 1230.0)  ; => #t
(eq?  123# 1230.0)  ; => #t