21222512 has 20 divisors (see below), whose sum is σ = 41205696. Its totient is φ = 10588800.

The previous prime is 21222503. The next prime is 21222529. The reversal of 21222512 is 21522212.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8513 + ... + 10719.

Almost surely, 2^21222512 is an apocalyptic number.

It is an amenable number.

21222512 is a deficient number, since it is larger than the sum of its proper divisors (19983184).

21222512 is a wasteful number, since it uses less digits than its factorization.

21222512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2816 (or 2810 counting only the distinct ones).

The product of its digits is 160, while the sum is 17.

The square root of 21222512 is about 4606.7897716306. The cubic root of 21222512 is about 276.8634306169.

Adding to 21222512 its reverse (21522212), we get a palindrome (42744724).

The spelling of 21222512 in words is "twenty-one million, two hundred twenty-two thousand, five hundred twelve".