28545665 has 8 divisors (see below), whose sum is σ = 34433448. Its totient is φ = 22717440.

The previous prime is 28545661. The next prime is 28545677. The reversal of 28545665 is 56654582.

It can be written as a sum of positive squares in 4 ways, for example, as 2729104 + 25816561 = 1652^2 + 5081^2 .

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

It is not a de Polignac number, because 28545665 - 2² = 28545661 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28545661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13826 + ... + 15755.

It is an arithmetic number, because the mean of its divisors is an integer number (4304181).

Almost surely, 2^28545665 is an apocalyptic number.

It is an amenable number.

28545665 is a deficient number, since it is larger than the sum of its proper divisors (5887783).

28545665 is a wasteful number, since it uses less digits than its factorization.

28545665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29779.

The product of its digits is 288000, while the sum is 41.

The square root of 28545665 is about 5342.8143332892. The cubic root of 28545665 is about 305.6187921032.

The spelling of 28545665 in words is "twenty-eight million, five hundred forty-five thousand, six hundred sixty-five".