21221422 has 8 divisors (see below), whose sum is σ = 32859072. Its totient is φ = 10268400.

The previous prime is 21221419. The next prime is 21221429. The reversal of 21221422 is 22412212.

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

It is a junction number, because it is equal to n+sod(n) for n = 21221396 and 21221405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221429) by changing a digit.

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, 171079 + ... + 171202.

It is an arithmetic number, because the mean of its divisors is an integer number (4107384).

Almost surely, 2^21221422 is an apocalyptic number.

21221422 is a deficient number, since it is larger than the sum of its proper divisors (11637650).

21221422 is a wasteful number, since it uses less digits than its factorization.

21221422 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342314.

The product of its digits is 128, while the sum is 16.

The square root of 21221422 is about 4606.6714664712. The cubic root of 21221422 is about 276.8586905825.

Adding to 21221422 its reverse (22412212), we get a palindrome (43633634).

The spelling of 21221422 in words is "twenty-one million, two hundred twenty-one thousand, four hundred twenty-two".