21222136 has 16 divisors (see below), whose sum is σ = 42852600. Its totient is φ = 9794784.

The previous prime is 21222043. The next prime is 21222143. The reversal of 21222136 is 63122212.

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, 101926 + ... + 102133.

Almost surely, 2^21222136 is an apocalyptic number.

21222136 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21222136 is an abundant number, since it is smaller than the sum of its proper divisors (21630464).

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

21222136 is a wasteful number, since it uses less digits than its factorization.

21222136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204078 (or 204074 counting only the distinct ones).

The product of its digits is 288, while the sum is 19.

The square root of 21222136 is about 4606.7489621207. The cubic root of 21222136 is about 276.8617955408.

Adding to 21222136 its reverse (63122212), we get a palindrome (84344348).

The spelling of 21222136 in words is "twenty-one million, two hundred twenty-two thousand, one hundred thirty-six".