28500557 has 8 divisors (see below), whose sum is σ = 28880280. Its totient is φ = 28123200.

The previous prime is 28500553. The next prime is 28500569. The reversal of 28500557 is 75500582.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 12348196 + 16152361 = 3514^2 + 4019^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28500557 - 2² = 28500553 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28500553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40307 + ... + 41007.

It is an arithmetic number, because the mean of its divisors is an integer number (3610035).

Almost surely, 2^28500557 is an apocalyptic number.

It is an amenable number.

28500557 is a deficient number, since it is larger than the sum of its proper divisors (379723).

28500557 is a wasteful number, since it uses less digits than its factorization.

28500557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1183.

The product of its (nonzero) digits is 14000, while the sum is 32.

The square root of 28500557 is about 5338.5912935905. The cubic root of 28500557 is about 305.4577271295.

The spelling of 28500557 in words is "twenty-eight million, five hundred thousand, five hundred fifty-seven".