28709187 has 16 divisors (see below), whose sum is σ = 41653920. Its totient is φ = 17482752.

The previous prime is 28709173. The next prime is 28709189. The reversal of 28709187 is 78190782.

It is not a de Polignac number, because 28709187 - 2⁸ = 28708931 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28709189) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12 + ... + 7577.

It is an arithmetic number, because the mean of its divisors is an integer number (2603370).

Almost surely, 2^28709187 is an apocalyptic number.

28709187 is a deficient number, since it is larger than the sum of its proper divisors (12944733).

28709187 is a wasteful number, since it uses less digits than its factorization.

28709187 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7702.

The product of its (nonzero) digits is 56448, while the sum is 42.

The square root of 28709187 is about 5358.0954638752. The cubic root of 28709187 is about 306.2012538269.

The spelling of 28709187 in words is "twenty-eight million, seven hundred nine thousand, one hundred eighty-seven".