28485209 has 2 divisors, whose sum is σ = 28485210. Its totient is φ = 28485208.

The previous prime is 28485203. The next prime is 28485239. The reversal of 28485209 is 90258482.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23309584 + 5175625 = 4828^2 + 2275^2 .

It is a cyclic number.

It is not a de Polignac number, because 28485209 - 2¹² = 28481113 is a prime.

It is a super-2 number, since 2×28485209² = 1622814263547362, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28485203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14242604 + 14242605.

It is an arithmetic number, because the mean of its divisors is an integer number (14242605).

Almost surely, 2^28485209 is an apocalyptic number.

It is an amenable number.

28485209 is a deficient number, since it is larger than the sum of its proper divisors (1).

28485209 is an equidigital number, since it uses as much as digits as its factorization.

28485209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 46080, while the sum is 38.

The square root of 28485209 is about 5337.1536421580. The cubic root of 28485209 is about 305.4028860142.

The spelling of 28485209 in words is "twenty-eight million, four hundred eighty-five thousand, two hundred nine".