28493639393 has 4 divisors (see below), whose sum is σ = 28675127700. Its totient is φ = 28312151088.

The previous prime is 28493639387. The next prime is 28493639443. The reversal of 28493639393 is 39393639482.

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 3930286864 + 24563352529 = 62692^2 + 156727^2 .

It is a cyclic number.

It is not a de Polignac number, because 28493639393 - 2²⁴ = 28476862177 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28493639303) 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, 90743918 + ... + 90744231.

It is an arithmetic number, because the mean of its divisors is an integer number (7168781925).

Almost surely, 2^28493639393 is an apocalyptic number.

It is an amenable number.

28493639393 is a deficient number, since it is larger than the sum of its proper divisors (181488307).

28493639393 is a wasteful number, since it uses less digits than its factorization.

28493639393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181488306.

The product of its digits is 22674816, while the sum is 59.

The spelling of 28493639393 in words is "twenty-eight billion, four hundred ninety-three million, six hundred thirty-nine thousand, three hundred ninety-three".