1281728 has 28 divisors (see below), whose sum is σ = 2907792. Its totient is φ = 549120.

The previous prime is 1281727. The next prime is 1281739. The reversal of 1281728 is 8271821.

It is a tau number, because it is divible by the number of its divisors (28).

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 1281728.

It is not an unprimeable number, because it can be changed into a prime (1281727) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 983 + ... + 1878.

2^1281728 is an apocalyptic number.

It is an amenable number.

1281728 is an abundant number, since it is smaller than the sum of its proper divisors (1626064).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1281728 is an equidigital number, since it uses as much as digits as its factorization.

1281728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2880 (or 2870 counting only the distinct ones).

The product of its digits is 1792, while the sum is 29.

The square root of 1281728 is about 1132.1342676556. The cubic root of 1281728 is about 108.6255422106.

The spelling of 1281728 in words is "one million, two hundred eighty-one thousand, seven hundred twenty-eight".