28618685 has 4 divisors (see below), whose sum is σ = 34342428. Its totient is φ = 22894944.

The previous prime is 28618663. The next prime is 28618703. The reversal of 28618685 is 58681682.

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 7431076 + 21187609 = 2726^2 + 4603^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28618685 is a prime.

It is a super-2 number, since 2×28618685² = 1638058262258450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2861864 + ... + 2861873.

It is an arithmetic number, because the mean of its divisors is an integer number (8585607).

Almost surely, 2^28618685 is an apocalyptic number.

It is an amenable number.

28618685 is a deficient number, since it is larger than the sum of its proper divisors (5723743).

28618685 is an equidigital number, since it uses as much as digits as its factorization.

28618685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5723742.

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

The square root of 28618685 is about 5349.6434460626. The cubic root of 28618685 is about 305.8791618511.

The spelling of 28618685 in words is "twenty-eight million, six hundred eighteen thousand, six hundred eighty-five".