28080209 has 8 divisors (see below), whose sum is σ = 29865960. Its totient is φ = 26309376.

The previous prime is 28080181. The next prime is 28080211. The reversal of 28080209 is 90208082.

It can be written as a sum of positive squares in 4 ways, for example, as 19360000 + 8720209 = 4400^2 + 2953^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28080209 - 2²⁰ = 27031633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28080229) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 287 + ... + 7499.

It is an arithmetic number, because the mean of its divisors is an integer number (3733245).

Almost surely, 2^28080209 is an apocalyptic number.

It is an amenable number.

28080209 is a deficient number, since it is larger than the sum of its proper divisors (1785751).

28080209 is a wasteful number, since it uses less digits than its factorization.

28080209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7459.

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 28080209 is about 5299.0762402517. The cubic root of 28080209 is about 303.9485752407.

The spelling of 28080209 in words is "twenty-eight million, eighty thousand, two hundred nine".