Round Thousand
Three zeros at the tail — presence established.
A multiple of 1000 (starting at 1000 itself) — the last three digits are all 0, like 7000, 500000 or 1000000.
Your record
From 1000 to 1,000,000 there are exactly 1,000 round thousands, 0.1% of the range — “one in a thousand” is not a figure of speech here but the literal hit probability.
Round thousands are secret members of the repetition family: the trailing 000 means every one of them is automatically a Triple, and one in ten (like 500000) ends in 0000, adding a Quad for free.
Human fondness for round numbers is baked into base ten — prices, populations and milestones all gravitate to them. The range cap 1,000,000 is itself a round thousand, and also a perfect square (1000²) and a perfect cube (100³): a triple identity to close the range.