No, composite. All whole numbers ending in zero are composite.
The US does not have a Prime Minister, so there was no US Prime Minister in 1900.
As a product of its prime factors: 2*2*5*5*19 = 1900 or as 22*52*19 = 1900
19
It is: 22*52*19 = 1900
It is: 22*52*19 = 1900
1900 = 22 x 52 x 19
Monarch - Meiji Emperor, Emperor of Japan (1867-1912) Prime Minister - Yamagata Aritomo, Prime Minister of Japan (1898-1900) Ito Hirobumi, Prime Minister of Japan (1900-1901)
Australia did not have a Prime Minister yet in 1900. Australia was federated in 1901, and with federation came the Federal government and the office of Prime Minister. The first Prime Minister was Sir Edmund Barton.
22 x 52 x 19 = 1900
1900 = 22 x 52 x 191
2, 5 and 19
Marquis of Salisbury