28689864 has 32 divisors (see below), whose sum is σ = 81971520. Its totient is φ = 8197056.

The previous prime is 28689851. The next prime is 28689889. The reversal of 28689864 is 46898682.

It is a happy number.

It is an unprimeable number.

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, 85219 + ... + 85554.

It is an arithmetic number, because the mean of its divisors is an integer number (2561610).

Almost surely, 2^28689864 is an apocalyptic number.

28689864 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

28689864 is an abundant number, since it is smaller than the sum of its proper divisors (53281656).

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

28689864 is a wasteful number, since it uses less digits than its factorization.

28689864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170789 (or 170785 counting only the distinct ones).

The product of its digits is 1327104, while the sum is 51.

The square root of 28689864 is about 5356.2920010022. The cubic root of 28689864 is about 306.1325411559.

The spelling of 28689864 in words is "twenty-eight million, six hundred eighty-nine thousand, eight hundred sixty-four".