28206216 has 24 divisors (see below), whose sum is σ = 76392030. Its totient is φ = 9402048.

The previous prime is 28206209. The next prime is 28206221. The reversal of 28206216 is 61260282.

It can be written as a sum of positive squares in only one way, i.e., 22184100 + 6022116 = 4710^2 + 2454^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is a self number, because there is not a number n which added to its sum of digits gives 28206216.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 195805 + ... + 195948.

Almost surely, 2^28206216 is an apocalyptic number.

It is an amenable number.

28206216 is an abundant number, since it is smaller than the sum of its proper divisors (48185814).

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

28206216 is a wasteful number, since it uses less digits than its factorization.

28206216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391765 (or 391758 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 28206216 is about 5310.9524569516. The cubic root of 28206216 is about 304.4025426828.

Adding to 28206216 its reverse (61260282), we get a palindrome (89466498).

The spelling of 28206216 in words is "twenty-eight million, two hundred six thousand, two hundred sixteen".