As I wrote, the Ethnologue data seems very conservative to me, but it is a standard. The Wikipedia page I link to has other estimates. For English, the native speaker range is from 309 to 375 million.

Remember that there is a substantial US population for whom English is a second language. As I understand it, the Ethnologue count would not include those bi-lingual speakers. There are other counts for people who speak a language, whether it is their native language or not. The general rough figure for English then is 1.5 billion speakers.

The number of speakers of Indonesian now includes almost all Javanese, which is a completely different language. The language you refer to is Indonesian/Malay, which includes about 15 million people in Malaysia, South Thailand and northern Sumatra (Indonesia). The total number of native speakers is about 150 million. But a further 100 million are virtually bi-lingual in Indonesian/Malay and their native language.

I estimate that about 250 million people are either native speakers of Indonesian/Malay or are bi-lingual as is Obama. As you say Indonesian is not a minor language.

Based on 25 years work in Indonesia/Malaysia, my belief is that because Indonesia is a different civilization, knowing the language broadens the mind far more than does knowing Spanish or French, both of which share linguistic and cultural roots with English.