28547865 has 12 divisors (see below), whose sum is σ = 49483044. Its totient is φ = 15225504.

The previous prime is 28547839. The next prime is 28547903. The reversal of 28547865 is 56874582.

28547865 is a `hidden beast` number, since 28 + 547 + 86 + 5 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 17438976 + 11108889 = 4176^2 + 3333^2 .

It is not a de Polignac number, because 28547865 - 2⁶ = 28547801 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 634397 = 28547865 / (2 + 8 + 5 + 4 + 7 + 8 + 6 + 5).

It is a self number, because there is not a number n which added to its sum of digits gives 28547865.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 317154 + ... + 317243.

It is an arithmetic number, because the mean of its divisors is an integer number (4123587).

Almost surely, 2^28547865 is an apocalyptic number.

It is an amenable number.

28547865 is a deficient number, since it is larger than the sum of its proper divisors (20935179).

28547865 is a wasteful number, since it uses less digits than its factorization.

28547865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 634408 (or 634405 counting only the distinct ones).

The product of its digits is 537600, while the sum is 45.

The square root of 28547865 is about 5343.0202133250. The cubic root of 28547865 is about 305.6266431969.

The spelling of 28547865 in words is "twenty-eight million, five hundred forty-seven thousand, eight hundred sixty-five".