21230206 has 8 divisors (see below), whose sum is σ = 32385240. Its totient is φ = 10435128.

The previous prime is 21230203. The next prime is 21230213. The reversal of 21230206 is 60203212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21230206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21230203) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 89841 + ... + 90076.

It is an arithmetic number, because the mean of its divisors is an integer number (4048155).

Almost surely, 2^21230206 is an apocalyptic number.

21230206 is a deficient number, since it is larger than the sum of its proper divisors (11155034).

21230206 is a wasteful number, since it uses less digits than its factorization.

21230206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179978.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 21230206 is about 4607.6247677084. The cubic root of 21230206 is about 276.8968845558.

Adding to 21230206 its reverse (60203212), we get a palindrome (81433418).

The spelling of 21230206 in words is "twenty-one million, two hundred thirty thousand, two hundred six".