28008685 has 4 divisors (see below), whose sum is σ = 33610428. Its totient is φ = 22406944.

The previous prime is 28008683. The next prime is 28008689. The reversal of 28008685 is 58680082.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58680082 = 2 ⋅29340041.

It can be written as a sum of positive squares in 2 ways, for example, as 11703241 + 16305444 = 3421^2 + 4038^2 .

It is a cyclic number.

It is not a de Polignac number, because 28008685 - 2¹ = 28008683 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28008683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2800864 + ... + 2800873.

It is an arithmetic number, because the mean of its divisors is an integer number (8402607).

Almost surely, 2^28008685 is an apocalyptic number.

It is an amenable number.

28008685 is a deficient number, since it is larger than the sum of its proper divisors (5601743).

28008685 is an equidigital number, since it uses as much as digits as its factorization.

28008685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5601742.

The product of its (nonzero) digits is 30720, while the sum is 37.

The square root of 28008685 is about 5292.3232138636. The cubic root of 28008685 is about 303.6902901030.

The spelling of 28008685 in words is "twenty-eight million, eight thousand, six hundred eighty-five".