28728129 has 8 divisors (see below), whose sum is σ = 38329632. Its totient is φ = 19139360.

The previous prime is 28728121. The next prime is 28728151. The reversal of 28728129 is 92182782.

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 28728129 - 2³ = 28728121 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28728121) 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, 5362 + ... + 9284.

It is an arithmetic number, because the mean of its divisors is an integer number (4791204).

Almost surely, 2^28728129 is an apocalyptic number.

It is an amenable number.

28728129 is a deficient number, since it is larger than the sum of its proper divisors (9601503).

28728129 is a wasteful number, since it uses less digits than its factorization.

28728129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6367.

The product of its digits is 32256, while the sum is 39.

The square root of 28728129 is about 5359.8627780942. The cubic root of 28728129 is about 306.2685817408.

The spelling of 28728129 in words is "twenty-eight million, seven hundred twenty-eight thousand, one hundred twenty-nine".