This reminds me of an old Soviet joke:
A Chukcha applies for membership in the Union of Soviet Writers. He is asked what literature he is familiar with.
‘Have you read Pushkin, Chukcha?’
‘Have you read Dostoevsky?’
‘Chukcha, can you even read at all?’
The Chukcha gets mad and says, ‘Chukcha not reader, Chukcha writer!’
The pronounciation is "seengrafeas". Γγ and γκ are both pronounced as "ng" in the middle of the word, and γκ as "g" in the beginning of the word (there is no word beginning with a γγ).