28218206 has 4 divisors (see below), whose sum is σ = 42327312. Its totient is φ = 14109102.

The previous prime is 28218199. The next prime is 28218221. The reversal of 28218206 is 60281282.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7054550 + ... + 7054553.

It is an arithmetic number, because the mean of its divisors is an integer number (10581828).

Almost surely, 2^28218206 is an apocalyptic number.

28218206 is a deficient number, since it is larger than the sum of its proper divisors (14109106).

28218206 is a wasteful number, since it uses less digits than its factorization.

28218206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14109105.

The product of its (nonzero) digits is 3072, while the sum is 29.

The square root of 28218206 is about 5312.0811364285. The cubic root of 28218206 is about 304.4456687495.

Adding to 28218206 its reverse (60281282), we get a palindrome (88499488).

The spelling of 28218206 in words is "twenty-eight million, two hundred eighteen thousand, two hundred six".