It's about 350,000 times as heavy as a Battery (AAA)
In other words, 4,000 kilograms is 330,000 times the weight of a Battery (AAA), and the weight of a Battery (AAA) is 0.0000030 times that amount.(Alkaline)
An "AAA" size battery weighs 0.012 kilograms. Batteries are named by the American National Standards Institute (ANSI) Committee C18 and AAA batteries were given their name because they were smaller than the "AA" and "A" size batteries which were invented first.
It's about 550,000 times as heavy as an Eye (Human)
In other words, 4,000 kilograms is 560,000 times the weight of an Eye (Human), and the weight of an Eye (Human) is 0.0000018 times that amount.(adult)
A fully developed eye (in a person over the age of thirteen), weighs about 0.0071 kilograms. The pupil of the eye varies depending on the amount of light it is exposed to, but typically measures about 4 mm across.
It's about 700,000 times as heavy as a Quarter
In other words, 4,000 kilograms is 705,500 times the weight of a Quarter, and the weight of a Quarter is 0.000001417 times that amount.(United States quarter-dollar coin) (a.k.a. Quarter dollar, a.k.a. America the Beautiful quarter, a.k.a. two bits)
The America the Beautiful series quarters, which began to enter circulation in 2017, weigh 0.00567 kilograms each. In answer to the common riddle, there are 119 ridges around the edge of the coin in its current design.
It's about 800,000 times as heavy as a sheet of Paper
In other words, 4,000 kilograms is 800,000 times the weight of a sheet of Paper, and the weight of a sheet of Paper is 0.0000013 times that amount.(for US Letter, a.k.a. ANSI A; 215.9mm by 279.4mm (8.5 in x 11 in); 20lb)
The weight of a ream (500 sheets) of 9.10 kilograms, 8.5 inch x 11 inch paper is 2 kg, each sheet weighing 0.005 kilograms. Paper of this size has a thickness of 0.004 caliper (0.1 mm).
It's about 1,000,000 times as heavy as a Die (Dice)
In other words, 4,000 kilograms is 980,000 times the weight of a Die (Dice), and the weight of a Die (Dice) is 0.00000100 times that amount.(for six-sided, 16 mm, rounded cube)
A die, of the size most commonly used in board games and casinos, typically weight 0.0041 kilograms. The use of dice and dice-like tools predates written history, with the oldest known examples belonging to a 5,000-year old backgammon set uncovered during an archaeological dig in modern-day Iran.
It's about 0.0000007 times as heavy as The Great Pyramid of Giza
In other words, 4,000 kilograms is 0.00000068 times the weight of The Great Pyramid of Giza, and the weight of The Great Pyramid of Giza is 1,500,000 times that amount.(a.k.a. Pyramid of Khufu, a.k.a. Pyramid of Cheops) (Cairo, Egypt)
The Great Pyramid of Giza has an estimated mass of 5,900,000,000 kilograms. The 2,300,000 stones used in the construction of the pyramid weighed an average 2,300 kilograms and were quarried from distances of up to 805 km (500 mi) away.
It's about 1,500,000 times as heavy as a Penny
In other words, 4,000 kilograms is 1,600,000 times the weight of a Penny, and the weight of a Penny is 0.00000063 times that amount.(United States) (formally one-cent coin) (Union shield design, 2010-present)
The weight of a United States penny is 0.0025 kilograms. According to a 2010 report by the United States Mint, the cost of manufacturing and distributing a penny is $0.0179 — more than its face-value.