If we discount colonial holdings not in the immediate theater; such as the Horn of Africa, British Somaliland, Middle Eastern holdings, etc then we must conclude the Italians had a an astounding local superiority in numbers. The Italians had the entirety of the 10th Army in North Africa at the beginning of the conflict; the British had the "Western Desert Force" which was a small, corps-sized force based on the 4th Indian Infantry Division and the 7th Armoured Division.

By contrast the 10th Army was a full sized, traditional army formation. Its commander was Marshal Graziani, who sums up Italy's half-hearted offensive quite nicely:

From the harsh experiences of these bitter days we must conclude that in this theater o fwar a single armored division is more powerful than a whole army

Jack Greene and Alessandro Massignani in their Rommel's North Africa Campaign explain the magnitude of the Italian defeat in 1940 by putting the disparity in numbers in clear focus. This should give you a good idea of the relative troop numbers:

The paper strength of an Italian metropolitan Infantry division was two regiments of three battalions each of infantry, a machine gun battalion, and three battalions of artillery...a total of 11, 000 men were in a division...

The 10th Army had 4 infantry divisions (a large corps) at Siddi Barrani before disaster struck; about 44, 000 men. Green et Al. state that the 10th Army had 4 corps of similar size; so if we account for army-level formations and support units, etc, its reasonable to estimate the 10th Army's strength at around 150, 000 men; a fairly typical Army size.

By contrast, the British TO and E for this time period had Infantry divisions at around 14, 000 men, and armored divisions at around 10, 000. The Western Desert Force, at the start of Operation Compass (the counterattack against the Italian 10th Army) would've numbered approximately 24, 000 men.