21022206 has 8 divisors (see below), whose sum is σ = 42044424. Its totient is φ = 7007400.

The previous prime is 21022193. The next prime is 21022213. The reversal of 21022206 is 60222012.

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

21022206 is an admirable number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1751845 + ... + 1751856.

It is an arithmetic number, because the mean of its divisors is an integer number (5255553).

Almost surely, 2^21022206 is an apocalyptic number.

21022206 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21022206 is a wasteful number, since it uses less digits than its factorization.

21022206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3503706.

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 21022206 is about 4584.9979280257. The cubic root of 21022206 is about 275.9896288899.

Adding to 21022206 its reverse (60222012), we get a palindrome (81244218).

The spelling of 21022206 in words is "twenty-one million, twenty-two thousand, two hundred six".