28728028 has 24 divisors (see below), whose sum is σ = 60836832. Its totient is φ = 11587584.

The previous prime is 28728023. The next prime is 28728061. The reversal of 28728028 is 82082782.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28728023) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29701 + ... + 30652.

It is an arithmetic number, because the mean of its divisors is an integer number (2534868).

Almost surely, 2^28728028 is an apocalyptic number.

28728028 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

28728028 is an abundant number, since it is smaller than the sum of its proper divisors (32108804).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28728028 is a wasteful number, since it uses less digits than its factorization.

28728028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60381 (or 60379 counting only the distinct ones).

The product of its (nonzero) digits is 28672, while the sum is 37.

The square root of 28728028 is about 5359.8533562029. The cubic root of 28728028 is about 306.2682228224.

The spelling of 28728028 in words is "twenty-eight million, seven hundred twenty-eight thousand, twenty-eight".