OFFSET
1,2
COMMENTS
The prime factorization of 10^9 + 1 = 7 * 11 * 13 * 19 * 52579, so tau(1000000001) = 2^5 = 32. - Bernard Schott, Oct 18 2019
EXAMPLE
7 * 142857143 = 1000000001.
11 * 90909091 = 1000000001.
13 * 76923077 = 1000000001.
MATHEMATICA
Divisors[10^9 + 1] (* Alonso del Arte, Oct 11 2019 *)
PROG
(PARI) divisors(10^9+1) \\ Charles R Greathouse IV, Jun 23 2017
CROSSREFS
KEYWORD
nonn,fini,full,easy
AUTHOR
STATUS
approved