28438598987 has 4 divisors (see below), whose sum is σ = 28720169376. Its totient is φ = 28157028600.

The previous prime is 28438598953. The next prime is 28438598999. The reversal of 28438598987 is 78989583482.

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

It is a cyclic number.

It is not a de Polignac number, because 28438598987 - 2¹⁴ = 28438582603 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 28438598987.

It is not an unprimeable number, because it can be changed into a prime (28438598917) 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, 140785043 + ... + 140785244.

It is an arithmetic number, because the mean of its divisors is an integer number (7180042344).

Almost surely, 2^28438598987 is an apocalyptic number.

28438598987 is a deficient number, since it is larger than the sum of its proper divisors (281570389).

28438598987 is a wasteful number, since it uses less digits than its factorization.

28438598987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281570388.

The product of its digits is 278691840, while the sum is 71.

The spelling of 28438598987 in words is "twenty-eight billion, four hundred thirty-eight million, five hundred ninety-eight thousand, nine hundred eighty-seven".