It is a tau number, because it is divible by the number of its divisors (168).
It is an unprimeable number.
21428840 is an apocalyptic number.
1428840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.
It is an amenable number.
It is a practical number, because each smaller number is the sum of distinct divisors of 1428840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2803545).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
1428840 is an equidigital number, since it uses as much as digits as its factorization.
1428840 is an odious number, because the sum of its binary digits is odd.
The square root of 1428840 is about 1195.3409555436. The cubic root of 1428840 is about 112.6318454222.
The spelling of 1428840 in words is "one million, four hundred twenty-eight thousand, eight hundred forty".