28687685 has 8 divisors (see below), whose sum is σ = 37073400. Its totient is φ = 21184704.

The previous prime is 28687667. The next prime is 28687697. The reversal of 28687685 is 58678682.

It can be written as a sum of positive squares in 4 ways, for example, as 289444 + 28398241 = 538^2 + 5329^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28687685 - 2⁸ = 28687429 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 220610 + ... + 220739.

It is an arithmetic number, because the mean of its divisors is an integer number (4634175).

Almost surely, 2^28687685 is an apocalyptic number.

It is an amenable number.

28687685 is a deficient number, since it is larger than the sum of its proper divisors (8385715).

28687685 is a wasteful number, since it uses less digits than its factorization.

28687685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 441367.

The product of its digits is 1290240, while the sum is 50.

The square root of 28687685 is about 5356.0885915003. The cubic root of 28687685 is about 306.1247906870.

The spelling of 28687685 in words is "twenty-eight million, six hundred eighty-seven thousand, six hundred eighty-five".