The phrase "altogether extraordinary" is correct and usable in written English.
It can be used to emphasize that something is completely or entirely remarkable or impressive.
Example: "The performance was altogether extraordinary, leaving the audience in awe."
Alternatives: "truly remarkable" or "completely exceptional."
In 1975, the respirator that kept Karen Ann Quinlan alive seemed, to her parents, altogether extraordinary.
When the Inland Revenue sued him, the judge described Mr Ecclestone's "machinery" as "altogether extraordinary", and ruled that he had breached company law.
Calling the challenge of providing security for the crowded area around the Garden "altogether extraordinary," the court said the city had not violated the First Amendment when it restricted the protesters to a demonstration zone on Eighth Avenue.
In 1927 Zabūr-e ʿAjam ("Persian Psalms") appeared, about which A.J. Arberry, its translator into English, wrote that "Iqbal displayed here an altogether extraordinary talent for the most delicate and delightful of all Persian styles, the ghazal," or love poem.
From the first rockets vaulting out of the city as the marines moved in, the noise and feel of the battle seemed altogether extraordinary; at other times, hardly real at all.
With choice accompaniment by the capable Southern rock visionaries Drive By Truckers and a sound often pushed into over drive by the volcanic lead guitar of rock & roll legend Neil Young, it is an altogether extraordinary set.
Then Manchester United would have expected a siege – what they got was something altogether more extraordinary.
But Angelo's needs don't altogether explain the extraordinary power of both these new characters: Mariana, who generated two poems by Tennyson, and Barnardine, who prompted the 19th-century notion that Shakespeare left the character alive because he liked him too much to kill him.
Extraordinary claims, after all, require extraordinary evidence.
That Republicans even find themselves in such a quandary just over two months after Mr. Trump was sworn in is at once extraordinary and not altogether surprising.
The wonder we feel is not at Cleopatra's beauty (which Plutarch reports was "in itself not altogether incomparable") but at the extraordinary cultural universe that preceded her and surrounded her before Egypt submitted to the Romans in 30 B.C. and Cleopatra — Egypt's last pharaoh and the end of the Ptolemaic dynasty — committed suicide.
