28548999909 has 20 divisors (see below), whose sum is σ = 42723905004. Its totient is φ = 18998466624.

The previous prime is 28548999893. The next prime is 28548999931. The reversal of 28548999909 is 90999984582.

It can be written as a sum of positive squares in 2 ways, for example, as 5255525025 + 23293474884 = 72495^2 + 152622^2 .

It is not a de Polignac number, because 28548999909 - 2⁴ = 28548999893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28548999989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 271272 + ... + 361505.

Almost surely, 2^28548999909 is an apocalyptic number.

It is an amenable number.

28548999909 is a deficient number, since it is larger than the sum of its proper divisors (14174905095).

28548999909 is an equidigital number, since it uses as much as digits as its factorization.

28548999909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 633346 (or 633337 counting only the distinct ones).

The product of its (nonzero) digits is 151165440, while the sum is 72.

The spelling of 28548999909 in words is "twenty-eight billion, five hundred forty-eight million, nine hundred ninety-nine thousand, nine hundred nine".