Is the word sessenta the same in Brazilian and European Portuguese?

Yes

The word "sessenta" is identical in meaning, spelling, and grammar in both Brazilian and Continental Portuguese. The only difference is in pronunciation.

In Brazilian Portuguese, the vowels are more "open" and the rhythm is more syllable-timed. The "e" sounds are clearly articulated and audible. In Continental Portuguese, the vowels are more "closed" or reduced. Unstressed vowels are often swallowed or pronounced as a very short, neutral sound, making the word sound more "staccato" and the vowels much more subtle.

Brazilian Portuguese Examples

1. Eu tenho sessenta anos. (I am sixty years old.)
2. O preço é sessenta reais. (The price is sixty reais.)
3. Ele leu sessenta páginas hoje. (He read sixty pages today.)
4. Naquela rua tem sessenta casas. (There are sixty houses on that street.)
5. Essa estrada tem sessenta quilômetros. (This road is sixty kilometers long.)

Continental Portuguese Examples

1. Eu tenho sessenta anos. (I am sixty years old.)
2. O preço é sessenta euros. (The price is sixty euros.)
3. Ele leu sessenta páginas hoje. (He read sixty pages today.)
4. Naquela rua há sessenta casas. (There are sixty houses on that street.)
5. Essa estrada tem sessenta quilómetros. (This road is sixty kilometers long.)