28985509 has 12 divisors (see below), whose sum is σ = 34128864. Its totient is φ = 24541944.

The previous prime is 28985503. The next prime is 28985519. The reversal of 28985509 is 90558982.

It is not a de Polignac number, because 28985509 - 2⁵ = 28985477 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28985503) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 504 + ... + 7630.

It is an arithmetic number, because the mean of its divisors is an integer number (2844072).

Almost surely, 2^28985509 is an apocalyptic number.

It is an amenable number.

28985509 is a deficient number, since it is larger than the sum of its proper divisors (5143355).

28985509 is an equidigital number, since it uses as much as digits as its factorization.

28985509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7224 (or 7217 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 46.

The square root of 28985509 is about 5383.8191834422. The cubic root of 28985509 is about 307.1805005448.

The spelling of 28985509 in words is "twenty-eight million, nine hundred eighty-five thousand, five hundred nine".