Was his father a US Cititzen?
NO, his father was never a citizen.
I don’t believe so.
The Social Security Administration (SSA) has a new process for noncitizens to apply for Social Security number (SSN) cards as part of the immigration process. Now, people age 18 and older applying for immigrant visas with the U.S. Department of State can also apply for SSN cards at the same time.
Obama, Sr. was never a US resident/Green Card holder. He was a BRITISH citizen and held a UKC Passport when Jr. was born. He was here on a student visa. If I am correct all students are required to be issued a valid SS number.
Obama, Sr. died 24 November 1982 but worked for a U.S. oil company. He had a SS number!
At Harvard, Obama, Sr. meet an American teacher, Ruth Nidesand. Later they moved to Kenya where they were reportedly married.[1] In Kenya he worked for a period of time with a U.S. oil company. Later he joined the government of Jomo Kenyatta,