280000

280000 is a natural number that follows 279999 and precedes 280001. In decimal form, it is a round figure ending with four zeros.

Mathematical properties of 280000 include its being even and composite. Its prime factorization is 2^6 × 5^4 × 7, which implies the number is divisible by 2, 4, 8, 16, 5, 10, 20, and many other multiples arising from these prime powers. The total number of positive divisors is (6+1)×(4+1)×(1+1) = 70. The sum of all divisors is (2^7−1)/(2−1) × (5^5−1)/(5−1) × (7^2−1)/(7−1) = 127 × 781 × 8 = 793,496, so the sum of proper divisors is 793,496 − 280000 = 513,496. Because the sum of proper divisors exceeds the number itself, 280000 is an abundant number.

Representations and usage of 280000 include its expression as 2.8 × 10^5 in scientific notation. The trailing zeros reflect its factorization by powers of 2 and 5, and its divisibility by 10^4 confirms a high level of decimal divisibility. As a rounded, easily recognizable figure, 280000 frequently appears in calculations, budgeting milestones, statistics, and other contexts requiring large, simple multiples of ten.

See also: related round numbers, such as powers of ten and products involving 2 and 5.