28287520 has 24 divisors (see below), whose sum is σ = 66829644. Its totient is φ = 11314944.

The previous prime is 28287503. The next prime is 28287521. The reversal of 28287520 is 2578282.

It can be written as a sum of positive squares in 2 ways, for example, as 25765776 + 2521744 = 5076^2 + 1588^2 .

It is not an unprimeable number, because it can be changed into a prime (28287521) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 88239 + ... + 88558.

Almost surely, 2^28287520 is an apocalyptic number.

28287520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28287520 is an abundant number, since it is smaller than the sum of its proper divisors (38542124).

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

28287520 is a wasteful number, since it uses less digits than its factorization.

28287520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176812 (or 176804 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 34.

The square root of 28287520 is about 5318.6013198960. The cubic root of 28287520 is about 304.6947407177.

The spelling of 28287520 in words is "twenty-eight million, two hundred eighty-seven thousand, five hundred twenty".