287728 has 30 divisors (see below), whose sum is σ = 650256. Its totient is φ = 122976.

The previous prime is 287701. The next prime is 287731. The reversal of 287728 is 827782.

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

It is a junction number, because it is equal to n+sod(n) for n = 287693 and 287702.

It is a congruent number.

It is an unprimeable number.

287728 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 601 + ... + 967.

2²⁸⁷⁷²⁸ is an apocalyptic number.

287728 is a gapful number since it is divisible by the number (28) 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 287728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (325128).

287728 is an abundant number, since it is smaller than the sum of its proper divisors (362528).

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

287728 is a wasteful number, since it uses less digits than its factorization.

287728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 389 (or 376 counting only the distinct ones).

The product of its digits is 12544, while the sum is 34.

The square root of 287728 is about 536.4028336987. The cubic root of 287728 is about 66.0177485172.

The spelling of 287728 in words is "two hundred eighty-seven thousand, seven hundred twenty-eight".