Composite.
621 is not prime. 621 = 3 * 3 * 3 * 23
621 is a composite number. A prime number has only 2 factors which are 1 and itself. Composite numbers are everything else except 1 and 0. 1 and 0 have a different name.
It is composite. It is divisible by 3, 9, 23, 27, 69, and 207.
Yes, the sum of 273 and 348 is 621.
yes
yes
2 percent of 621 = 12.422% of 621= 2% * 621= 0.02 * 621= 12.42
Yes, but the product results in a floating point number, ie a decimal point. 621 ÷ 2 = 310.5
Yes
Yes, exactly 207 times
Yes, they are relatively prime.