I heard this very long ago that while is Sajood, we can praise Allah 3 times, I sometimes make my sujood long like in odd numbers but recently stopped as I wasn't sure if it is allowed or not. Is there any saying about odd times of glorifying Allah in ruku and sujood?
The matter is wide open:
You could say it three times, you could say it more you could say it even less. And you could perform du'a (See in Sahih Muslim) instead of praising Allah during sujud.
If you performed it once and in all unhurriedly it would be regarded as valid. The main reason for considering praising Allah three times sunnah are ahadith such as:
It was narrated from Hudhaifah bin Al-Yaman that he heard the Messenger of Allah (ﷺ) say when he bowed:
“Subhana Rabbiyal-‘Azim (Glory is to my Lord, the Most Great)” three times, and when he prostrated he said: “Subhana Rabbiyal-A’la (Glory is to my Lord the Most High)” three times.
(See in Sunan ibn Majah and other Variations in Sunan abi Dawod 1, 2)
Note that a main reason for declaring many of these variations as da'if is the addition that appears in Sunan abi Dawod and also in Sunan ibn Majah saying:
This is the minimum number.
However their are narrations that don't specify an amount like:
... And when he prostrated he said: "Subahana Rabbial-A'la, Subahna Rabbial-A'la (Glory be to my Lord Most High, glory be to my Lord Most High)." ...
(See for example in Sunan an-Nasa-i)
all scholars agrees you can do it more than 3 times! Imam Ahmed says in his Fiqh book you should say it 7 times and he uses the proof that in the athkar of the Prophets, the best remembrance are done 7 times.
But I prefer to say 3 times but add other athkar in Ruku and Dua in sujood!
You can find these in this prayer book