I write 620 billion as 620 billion.
You write 3.56 billion as 3,560,000,000.
1,000 billion billion is: 1,000,000,000,000,000,000,000
u write four billion like 4,0000,000,000
Ways to write one billion is: one billion,1 billion,1,000,000,000,you can write it in roman numeral several different ways,with tally marks, etc.
200 billion billion in numerals is: 200,000,000,000,000,000,000
how to write 5.1 billion
Assuming you mean billion*billion*billion = It is 1*10^27.
In word forms, you can write it as 20 billion dollars, twenty billion dollars, $20 billion. Or you can write it as $20,000,000,000. There are at least 4 ways to write it, and probably more.
Since you asked how I would write the number, the answer is 1031.
you can write seven billion either worded or as numbers here are some examples: seven billion or 7,000,000,000
Sixteen point two billion is how I would write it.
three billion - 3,000,000,000
12.7 billion = 12,700,000,000
8.1 billion = 8,100,000,000
1.69 billion = 1,690,000,000
ten billion is 10,000,000,000 .
1.2 billion is 1,200,000,000 .
forty billion 40,000,000,000
1 billion = 1,000,000,000
7.2 billion = 7,200,000,000
ten billion 10,000,000,000.00