28288733 has 4 divisors (see below), whose sum is σ = 30860448. Its totient is φ = 25717020.

The previous prime is 28288703. The next prime is 28288747. The reversal of 28288733 is 33788282.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28288733 - 2¹⁰ = 28287709 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28288703) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1285841 + ... + 1285862.

It is an arithmetic number, because the mean of its divisors is an integer number (7715112).

Almost surely, 2^28288733 is an apocalyptic number.

It is an amenable number.

28288733 is a deficient number, since it is larger than the sum of its proper divisors (2571715).

28288733 is a wasteful number, since it uses less digits than its factorization.

28288733 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2571714.

The product of its digits is 129024, while the sum is 41.

The square root of 28288733 is about 5318.7153524136. The cubic root of 28288733 is about 304.6990958708.

The spelling of 28288733 in words is "twenty-eight million, two hundred eighty-eight thousand, seven hundred thirty-three".