28288539 has 24 divisors (see below), whose sum is σ = 42474432. Its totient is φ = 18128880.

The previous prime is 28288537. The next prime is 28288541. The reversal of 28288539 is 93588282.

It is an interprime number because it is at equal distance from previous prime (28288537) and next prime (28288541).

It is not a de Polignac number, because 28288539 - 2¹ = 28288537 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 28288494 and 28288503.

It is not an unprimeable number, because it can be changed into a prime (28288531) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 25384 + ... + 26474.

It is an arithmetic number, because the mean of its divisors is an integer number (1769768).

Almost surely, 2^28288539 is an apocalyptic number.

28288539 is a deficient number, since it is larger than the sum of its proper divisors (14185893).

28288539 is a wasteful number, since it uses less digits than its factorization.

28288539 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1207 (or 1204 counting only the distinct ones).

The product of its digits is 276480, while the sum is 45.

The square root of 28288539 is about 5318.6971148957. The cubic root of 28288539 is about 304.6983993419.

The spelling of 28288539 in words is "twenty-eight million, two hundred eighty-eight thousand, five hundred thirty-nine".