Two hundred ten thousand.
21,000,000 is twenty one million.
It is: 2.1*10^7
10 percent of 21000000 is 2100000.
210000000
21000000
2.1 x 10^7
3000000 x 7 = 21000000
350,000 hours.
42000
it is worth $21000000
at least
2.1 X 10^7 The zeros are superfluous.