28728785 has 16 divisors (see below), whose sum is σ = 36088320. Its totient is φ = 21928320.

The previous prime is 28728769. The next prime is 28728787. The reversal of 28728785 is 58782782.

It is not a de Polignac number, because 28728785 - 2⁴ = 28728769 is a prime.

It is a super-3 number, since 3×28728785³ (a number of 23 digits) contains 333 as substring.

It is a Curzon number.

It is a nialpdrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (28728787) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10046 + ... + 12584.

It is an arithmetic number, because the mean of its divisors is an integer number (2255520).

Almost surely, 2^28728785 is an apocalyptic number.

It is an amenable number.

28728785 is a deficient number, since it is larger than the sum of its proper divisors (7359535).

28728785 is a wasteful number, since it uses less digits than its factorization.

28728785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2648.

The product of its digits is 501760, while the sum is 47.

The square root of 28728785 is about 5359.9239733414. The cubic root of 28728785 is about 306.2709129131.

The spelling of 28728785 in words is "twenty-eight million, seven hundred twenty-eight thousand, seven hundred eighty-five".