interval
D♯ perfect fifth
D♯lowerA♯upperP57 half steps
Seven half steps. Stack twelve of them and you land back where you started, give or take a comma.
On the keyboard
What is true of it
D♯ up a perfect fifth is A♯: 7 half steps, and 5 letters counting both ends.
Turn it upside down — put the D♯ on top — and it becomes a perfect fourth. The two numbers always add to nine, and the two sizes to twelve.
It is a perfect consonance.
Every interval on D♯
D♯ → Eminor second · dissonanceD♯ → E♯major second · dissonanceD♯ → F♯minor third · imperfect consonanceD♯ → F𝄪major third · imperfect consonanceD♯ → G♯perfect fourth · perfect consonanceD♯ → G𝄪augmented fourth · dissonanceD♯ → Adiminished fifth · dissonanceD♯ → Bminor sixth · imperfect consonanceD♯ → B♯major sixth · imperfect consonanceD♯ → C♯minor seventh · dissonanceD♯ → C𝄪major seventh · dissonance