28430665 has 4 divisors (see below), whose sum is σ = 34116804. Its totient is φ = 22744528.

The previous prime is 28430663. The next prime is 28430683. The reversal of 28430665 is 56603482.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10342656 + 18088009 = 3216^2 + 4253^2 .

It is a cyclic number.

It is not a de Polignac number, because 28430665 - 2¹ = 28430663 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28430665.

It is not an unprimeable number, because it can be changed into a prime (28430663) 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, 2843062 + ... + 2843071.

It is an arithmetic number, because the mean of its divisors is an integer number (8529201).

Almost surely, 2^28430665 is an apocalyptic number.

It is an amenable number.

28430665 is a deficient number, since it is larger than the sum of its proper divisors (5686139).

28430665 is an equidigital number, since it uses as much as digits as its factorization.

28430665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5686138.

The product of its (nonzero) digits is 34560, while the sum is 34.

The square root of 28430665 is about 5332.0413539282. The cubic root of 28430665 is about 305.2078311161.

The spelling of 28430665 in words is "twenty-eight million, four hundred thirty thousand, six hundred sixty-five".