I wrote a patch to compute stat about PyLong function calls.

make (use setup.py):

PyLong_FromLong: 168572 calls, min=( 0,  ), avg=(1.4,    ), max=(  3,    )
long_bool:        48682 calls, min=( 0,  ), avg=(0.2,    ), max=(  2,    )
long_add:         39527 calls, min=( 0, 0), avg=(0.9, 1.0), max=(  2,   3)
long_compare:     39145 calls, min=( 0, 0), avg=(1.2, 1.1), max=(  3,   3)
PyLong_AsLong:    33689 calls, min=( 0,  ), avg=(0.9,    ), max=( 45,    )
long_sub:         13091 calls, min=( 0, 0), avg=(0.9, 0.8), max=(  1,   1)
long_bitwise:      4636 calls, min=( 0, 0), avg=(0.8, 0.6), max=(  2,   2)
long_hash:         1097 calls, min=( 0,  ), avg=(0.9,    ), max=(  3,    )
long_mul:           221 calls, min=( 0, 0), avg=(0.8, 1.1), max=(  2,   2)
long_invert:        204 calls, min=( 0,  ), avg=(1.0,    ), max=(  1,    )
long_neg:            35 calls, min=( 1,  ), avg=(1.0,    ), max=(  1,    )
long_format:          3 calls, min=( 0,  ), avg=(0.7,    ), max=(  1,    )
long_mod:             3 calls, min=( 1, 1), avg=(1.0, 1.0), max=(  1,   1)
long_pow:             1 calls, min=( 1, 1), avg=(1.0, 1.0), max=(  1,   1)

pystone:

PyLong_FromLong:1587652 calls, min=( 0,  ), avg=(1.0,    ), max=(  3,    )
long_add:        902487 calls, min=( 0, 0), avg=(1.0, 1.0), max=(  2,   2)
long_compare:    651165 calls, min=( 0, 0), avg=(1.0, 1.0), max=(  3,   3)
PyLong_AsLong:   252476 calls, min=( 0,  ), avg=(1.0,    ), max=(  2,    )
long_sub:        250032 calls, min=( 1, 0), avg=(1.0, 1.0), max=(  1,   1)
long_bool:       102655 calls, min=( 0,  ), avg=(0.5,    ), max=(  1,    )
long_mul:        100015 calls, min=( 0, 0), avg=(1.0, 1.0), max=(  1,   2)
long_div:         50000 calls, min=( 1, 1), avg=(1.0, 1.0), max=(  1,   1)
long_hash:          382 calls, min=( 0,  ), avg=(1.1,    ), max=(  2,    )
long_bitwise:       117 calls, min=( 0, 0), avg=(1.0, 1.0), max=(  1,   2)
long_format:          1 calls, min=( 2,  ), avg=(2.0,    ), max=(  2,    )

min/avg/max are the integer digit count (minimum, average, maximum).

What can we learn from this numbers?

PyLong_FromLong(), long_add() and long_compare() are the 3 most common 
operations on integers. 

Except PyLong_FromLong(), long_compare() and long_format(), arguments of the 
functions are mostly in range [-2^15; 2^15].

Biggest number is a number of 45 digits: maybe just one call to long_add(). 
Except this number/call, the biggest numbers have between 2 and 3 digits. 

long_bool() is never called with number bigger than 2 digits.

long_sub() is never called with number bigger than 1 digit!