28809845 has 8 divisors (see below), whose sum is σ = 34660440. Its totient is φ = 22988800.

The previous prime is 28809841. The next prime is 28809887. The reversal of 28809845 is 54890882.

It can be written as a sum of positive squares in 4 ways, for example, as 12439729 + 16370116 = 3527^2 + 4046^2 .

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

It is not a de Polignac number, because 28809845 - 2² = 28809841 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 28809796 and 28809805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28809841) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5180 + ... + 9189.

It is an arithmetic number, because the mean of its divisors is an integer number (4332555).

Almost surely, 2^28809845 is an apocalyptic number.

It is an amenable number.

28809845 is a deficient number, since it is larger than the sum of its proper divisors (5850595).

28809845 is a wasteful number, since it uses less digits than its factorization.

28809845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14775.

The product of its (nonzero) digits is 184320, while the sum is 44.

The square root of 28809845 is about 5367.4803213426. The cubic root of 28809845 is about 306.5586963689.

The spelling of 28809845 in words is "twenty-eight million, eight hundred nine thousand, eight hundred forty-five".