How many years are there in one bimillennium

A bi-millennium means two (bi) times thousand of years (millenium), this means that a bi millennium has 2000 years in it: two thousand years. 

The origin of this word is latin: because of this it also has the plural of "bimillennia"   

38+105= 143, 39+104=143, and you will find then adding the numbers on opposite sides, moving inwards yields the answer 138 every time. because of this, you’re going to multiply 138 times the number of pairs, which is 34. therefore, 34*138= 4692(i’m sorry if it’s the wrong numbers, but it’s the right concept)