this article talks about the manvantara and it's swami (now is savarni), death/replacement of manu. The article also throws light on death/replacement of the creator god (Lord Bramha), the article also shows how hindu stories are scientifically sound and they both join at one end.
This even death of Bramha means that there is death for every god created in one Chaturyuga .
This is the exact time divisions for Gods.
1 human year (in Hindu calendar) = 1 Deva Ahoratra for God (1 day and 1 night)
360 Deva Ahoratras = 1 Deva Vatsara
12,000 Deva Vatsara = 1 Chaturyuga
(12,000 Deva Vatsaras are defined as, 4,800 Deva Vatsaras of Krita yuga, 3,600 Deva Vatsaras of Treta Yuga, 2,400 Deva Vatsaras of Dvapara Yuga and 1,200 Deva Vatsaras of Kali Yuga which is 1,200 * 360 = 4,32,000 human years)
71 Chaturyugas = 1 Manvantaram (1 life span of Manu)
14 Manvantaras = 1 kalpa (1 day of Brahma)
2 Kalpas = 1 day + 1 Brahma ratra
360 days of Brahma = 1 Brahma varsha
Talking about Indra it is a position reserved for the Bali who struggles and gives respect to the vamana avatar in every Chaturyuga. This article talks about the raja Bali.
Following is excrept from the article which is derived from Vamana Purana
which talks about next Indra as Raja Bali.
As he was pushed down into Patala (a good colony of demons), King Bali made a last request. He requested that he be allowed to visit Kerala once in a year to ensure that his people were still happy, well fed and content. Lord Vishnu was pleased to grant Mahabali his wish. Also, by the boon of Vishnu, Bali will be the next, that is the eighth Indra (King of Devas) (Purandara is the current Indra) during the time of the eighth Manu, Savarni Manu.
As you see from above discussion that we are not even equivalent to a second in a god's life cycle we have to Worship them as eternal in our lifetime and they will be automatically replaced by newer ones after their Lifecycle.
P.S: Talking about god's sun is also a god and will die after estimated life span of 12 billion years!
There are some interyugic cycle which Shri Yuketshwar Giri believes cycle in one yuga e.g.
Presently it is the age of kali yuga but in the kali-yuga(or any other yuga) there are 4 ages in it also known as sat,treta,dwapar,kali and each of them depicts the age of the dharma i.e. weather it is decline of righteousness or rise of it this cycle completes in 24000 years.
See this for more reading on this theory