28289806 has 4 divisors (see below), whose sum is σ = 42434712. Its totient is φ = 14144902.

The previous prime is 28289801. The next prime is 28289813. The reversal of 28289806 is 60898282.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60898282 = 2 ⋅30449141.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28289801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7072450 + ... + 7072453.

It is an arithmetic number, because the mean of its divisors is an integer number (10608678).

Almost surely, 2^28289806 is an apocalyptic number.

28289806 is a deficient number, since it is larger than the sum of its proper divisors (14144906).

28289806 is a wasteful number, since it uses less digits than its factorization.

28289806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14144905.

The product of its (nonzero) digits is 110592, while the sum is 43.

The square root of 28289806 is about 5318.8162216794. The cubic root of 28289806 is about 304.7029482643.

The spelling of 28289806 in words is "twenty-eight million, two hundred eighty-nine thousand, eight hundred six".