28709128 has 16 divisors (see below), whose sum is σ = 61519680. Its totient is φ = 12303888.

The previous prime is 28709113. The next prime is 28709173. The reversal of 28709128 is 82190782.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 256276 + ... + 256387.

It is an arithmetic number, because the mean of its divisors is an integer number (3844980).

Almost surely, 2^28709128 is an apocalyptic number.

28709128 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

28709128 is an abundant number, since it is smaller than the sum of its proper divisors (32810552).

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

28709128 is a wasteful number, since it uses less digits than its factorization.

28709128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 512676 (or 512672 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 37.

The square root of 28709128 is about 5358.0899581847. The cubic root of 28709128 is about 306.2010440696.

The spelling of 28709128 in words is "twenty-eight million, seven hundred nine thousand, one hundred twenty-eight".