28678673 has 4 divisors (see below), whose sum is σ = 28769460. Its totient is φ = 28587888.

The previous prime is 28678667. The next prime is 28678681. The reversal of 28678673 is 37687682.

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 9168784 + 19509889 = 3028^2 + 4417^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28678673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28678633) 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, 44918 + ... + 45551.

It is an arithmetic number, because the mean of its divisors is an integer number (7192365).

Almost surely, 2^28678673 is an apocalyptic number.

It is an amenable number.

28678673 is a deficient number, since it is larger than the sum of its proper divisors (90787).

28678673 is an equidigital number, since it uses as much as digits as its factorization.

28678673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90786.

The product of its digits is 677376, while the sum is 47.

The square root of 28678673 is about 5355.2472398574. The cubic root of 28678673 is about 306.0927318024.

Subtracting 28678673 from its reverse (37687682), we obtain a palindrome (9009009).

The spelling of 28678673 in words is "twenty-eight million, six hundred seventy-eight thousand, six hundred seventy-three".