28152509 has 24 divisors (see below), whose sum is σ = 37620000. Its totient is φ = 20774880.

The previous prime is 28152497. The next prime is 28152511. The reversal of 28152509 is 90525182.

It is not a de Polignac number, because 28152509 - 2¹⁶ = 28086973 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28152599) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8867 + ... + 11615.

It is an arithmetic number, because the mean of its divisors is an integer number (1567500).

Almost surely, 2^28152509 is an apocalyptic number.

It is an amenable number.

28152509 is a deficient number, since it is larger than the sum of its proper divisors (9467491).

28152509 is a wasteful number, since it uses less digits than its factorization.

28152509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2793 (or 2786 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 32.

The square root of 28152509 is about 5305.8937984095. The cubic root of 28152509 is about 304.2092172744.

The spelling of 28152509 in words is "twenty-eight million, one hundred fifty-two thousand, five hundred nine".