1428840 has 168 divisors, whose sum is σ = 5607090. Its totient is φ = 326592.

The previous prime is 1428839. The next prime is 1428851. The reversal of 1428840 is 488241.

It can be written as a sum of positive squares in only one way, i.e., 1285956 + 142884 = 1134^2 + 378^2 .

It is a tau number, because it is divible by the number of its divisors (168).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 41 ways as a sum of consecutive naturals, for example, 204117 + ... + 204123.

2^1428840 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).

1428840 is an abundant number, since it is smaller than the sum of its proper divisors (4178250).

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 sum of its prime factors is 43 (or 17 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 27.

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".