Also is there an easy method other than trial and error to figure out divisibility for other large numbers?
2007-10-20 12:13:17 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
3337 = 47*71.
Got this with the aid of PARI.
There are many methods to test if a number is
prime or not.
Probably the simplest is to use the contrapositive
of Fermat's little theorem:
a^(p-1) = 1(mod p) for every prime p.
So if a^(n-1) .ne. 1(mod n), then n is composite.
However, if a^(n-1) = 1(mod n) n is not
necessarily prime.
2^340 = 1(mod 341), but 341 is divisible by 11.
2007-10-20 12:28:14 · answer #1 · answered by steiner1745 7 · 2⤊ 0⤋
Um, it's divisible by one and 3337. Here are some simple rules: Divisible by two if ends in even number. Divisible by three if, when you add all digits together, the sum is divisible by three, Divisible by four if last two digits are divisble by four or 00. Divisible by five if last digit is five or zero. Divisible by six if divisible by two and three. Divisible by nine if sum of digits is divisible by nine. Divisible by ten if last digit is a zero. For large large numbers, I know of no shortcuts.
2007-10-20 12:17:48 · answer #2 · answered by Ra M 2 · 4⤊ 1⤋
Prime number,
Prime = Only can be divisible by itself.
2007-10-20 12:27:51 · answer #3 · answered by erikabby 2 · 0⤊ 1⤋
Try every prime number up to its square root.
2,3,5,7,11,13,17,19,23,29,
31,37,41,43,47,53,57
2007-10-20 12:25:26 · answer #4 · answered by ancient_nerd 2 · 0⤊ 0⤋
only 1 and 3337.
2007-10-20 12:22:37 · answer #5 · answered by bushnana 6 · 0⤊ 1⤋