28855009 has 4 divisors (see below), whose sum is σ = 28868400. Its totient is φ = 28841620.

The previous prime is 28855007. The next prime is 28855027. The reversal of 28855009 is 90055882.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28855009 - 2¹ = 28855007 is a prime.

It is a super-2 number, since 2×28855009² = 1665223088780162, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28855007) 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, 2647 + ... + 8044.

It is an arithmetic number, because the mean of its divisors is an integer number (7217100).

Almost surely, 2^28855009 is an apocalyptic number.

It is an amenable number.

28855009 is a deficient number, since it is larger than the sum of its proper divisors (13391).

28855009 is a wasteful number, since it uses less digits than its factorization.

28855009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13390.

The product of its (nonzero) digits is 28800, while the sum is 37.

The square root of 28855009 is about 5371.6858619990. The cubic root of 28855009 is about 306.7188058534.

The spelling of 28855009 in words is "twenty-eight million, eight hundred fifty-five thousand, nine".