21222006 has 24 divisors (see below), whose sum is σ = 45962280. Its totient is φ = 6529536.

The previous prime is 21221953. The next prime is 21222013. The reversal of 21222006 is 60022212.

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 11 ways as a sum of consecutive naturals, for example, 9451 + ... + 11478.

It is an arithmetic number, because the mean of its divisors is an integer number (1915095).

Almost surely, 2^21222006 is an apocalyptic number.

21222006 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21222006 is an abundant number, since it is smaller than the sum of its proper divisors (24740274).

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

21222006 is a wasteful number, since it uses less digits than its factorization.

21222006 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20960 (or 20947 counting only the distinct ones).

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

The square root of 21222006 is about 4606.7348523656. The cubic root of 21222006 is about 276.8612302174.

Adding to 21222006 its reverse (60022212), we get a palindrome (81244218).

The spelling of 21222006 in words is "twenty-one million, two hundred twenty-two thousand, six".