28613665 has 4 divisors (see below), whose sum is σ = 34336404. Its totient is φ = 22890928.

The previous prime is 28613621. The next prime is 28613671. The reversal of 28613665 is 56631682.

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 21307456 + 7306209 = 4616^2 + 2703^2 .

It is a cyclic number.

It is not a de Polignac number, because 28613665 - 2⁷ = 28613537 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 2861362 + ... + 2861371.

It is an arithmetic number, because the mean of its divisors is an integer number (8584101).

Almost surely, 2^28613665 is an apocalyptic number.

It is an amenable number.

28613665 is a deficient number, since it is larger than the sum of its proper divisors (5722739).

28613665 is an equidigital number, since it uses as much as digits as its factorization.

28613665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5722738.

The product of its digits is 51840, while the sum is 37.

The square root of 28613665 is about 5349.1742353376. The cubic root of 28613665 is about 305.8612760632.

The spelling of 28613665 in words is "twenty-eight million, six hundred thirteen thousand, six hundred sixty-five".