28217286 has 12 divisors (see below), whose sum is σ = 61137492. Its totient is φ = 9405756.

The previous prime is 28217257. The next prime is 28217327. The reversal of 28217286 is 68271282.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 28217286.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 783796 + ... + 783831.

It is an arithmetic number, because the mean of its divisors is an integer number (5094791).

Almost surely, 2^28217286 is an apocalyptic number.

28217286 is an abundant number, since it is smaller than the sum of its proper divisors (32920206).

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

28217286 is a wasteful number, since it uses less digits than its factorization.

28217286 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1567635 (or 1567632 counting only the distinct ones).

The product of its digits is 21504, while the sum is 36.

The square root of 28217286 is about 5311.9945406598. The cubic root of 28217286 is about 304.4423600929.

The spelling of 28217286 in words is "twenty-eight million, two hundred seventeen thousand, two hundred eighty-six".