28640206 has 24 divisors (see below), whose sum is σ = 52916976. Its totient is φ = 11551680.

The previous prime is 28640203. The next prime is 28640207. The reversal of 28640206 is 60204682.

It is a super-2 number, since 2×28640206² = 1640522799444872, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28640203) 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 in 11 ways as a sum of consecutive naturals, for example, 6930 + ... + 10261.

It is an arithmetic number, because the mean of its divisors is an integer number (2204874).

Almost surely, 2^28640206 is an apocalyptic number.

28640206 is a deficient number, since it is larger than the sum of its proper divisors (24276770).

28640206 is a wasteful number, since it uses less digits than its factorization.

28640206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17224 (or 17217 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 28.

The square root of 28640206 is about 5351.6545105229. The cubic root of 28640206 is about 305.9558154552.

Adding to 28640206 its reverse (60204682), we get a palindrome (88844888).

The spelling of 28640206 in words is "twenty-eight million, six hundred forty thousand, two hundred six".