Command line program written in C that calculates and prints the full prime factorization of a natural number (at least 2) using trial division.

Example outputs:

• 3 = 3
• 69 = 3 * 23
• 256 = 2 * 2 * 2 * 2 * 2 * 2 * 2 * 2
• 727 = 727
• 4294967295 = 3 * 5 * 17 * 257 * 65537
• 614889782588491410 = 2 * 3 * 5 * 7 * 11 * 13 * 17 * 19 * 23 * 29 * 31 * 37 * 41 * 43 * 47

The input is an unsigned 64-bit integer, so it works with any integer from 2 to 18446744073709551615 (2^64 - 1), inclusive.

Building requires a compiler, preferably GCC, and Make. Make sure to edit the makefile according to your compiler and OS. To build, open a command line and type make. You can then execute by typing ./primes <n> (on Unix-like systems) or primes <n> (on Windows), where <n> is the integer input, and clean by typing make clean.

Built for 64-bit systems by default, but you can edit the macros to change it to 32-bit.

Linux executable size: 15.9 KiB