28209536 has 32 divisors (see below), whose sum is σ = 56987400. Its totient is φ = 13906944.

The previous prime is 28209521. The next prime is 28209539. The reversal of 28209536 is 63590282.

It is a tau number, because it is divible by the number of its divisors (32).

It is a junction number, because it is equal to n+sod(n) for n = 28209496 and 28209505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28209539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7835 + ... + 10853.

Almost surely, 2^28209536 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28209536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28493700).

28209536 is an abundant number, since it is smaller than the sum of its proper divisors (28777864).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28209536 is an equidigital number, since it uses as much as digits as its factorization.

28209536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3106 (or 3094 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 35.

The square root of 28209536 is about 5311.2650093928. The cubic root of 28209536 is about 304.4144854025.

The spelling of 28209536 in words is "twenty-eight million, two hundred nine thousand, five hundred thirty-six".