28803 has 4 divisors (see below), whose sum is σ = 38408. Its totient is φ = 19200.
The previous prime is 28793. The next prime is 28807. The reversal of 28803 is 30882.
Added to its reverse (30882) it gives a triangular number (59685 = T345).
It is a semiprime because it is the product of two primes.
It is not a de Polignac number, because 28803 - 25 = 28771 is a prime.
It is a super-2 number, since 2×288032 = 1659225618, which contains 22 as substring.
It is a D-number.
It is a Duffinian number.
28803 is a lucky number.
It is a self number, because there is not a number n which added to its sum of digits gives 28803.
It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 28803.
It is not an unprimeable number, because it can be changed into a prime (28807) 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, 4798 + ... + 4803.
It is an arithmetic number, because the mean of its divisors is an integer number (9602).
228803 is an apocalyptic number.
28803 is a deficient number, since it is larger than the sum of its proper divisors (9605).
28803 is an equidigital number, since it uses as much as digits as its factorization.
28803 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 9604.
The product of its (nonzero) digits is 384, while the sum is 21.
The square root of 28803 is about 169.7144660894. The cubic root of 28803 is about 30.6534415774.
Subtracting from 28803 its sum of digits (21), we obtain a palindrome (28782).
Adding to 28803 its reverse (30882), we get a triangular number (59685 = T345).
The spelling of 28803 in words is "twenty-eight thousand, eight hundred three".
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