21322228 has 6 divisors (see below), whose sum is σ = 37313906. Its totient is φ = 10661112.

The previous prime is 21322207. The next prime is 21322229. The reversal of 21322228 is 82222312.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 21049744 + 272484 = 4588^2 + 522^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21322199 and 21322208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21322229) by changing a digit.

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 as a sum of consecutive naturals, namely, 2665275 + ... + 2665282.

Almost surely, 2^21322228 is an apocalyptic number.

It is an amenable number.

21322228 is a deficient number, since it is larger than the sum of its proper divisors (15991678).

21322228 is a wasteful number, since it uses less digits than its factorization.

21322228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5330561 (or 5330559 counting only the distinct ones).

The product of its digits is 768, while the sum is 22.

The square root of 21322228 is about 4617.5998094248. The cubic root of 21322228 is about 277.2963763367.

The spelling of 21322228 in words is "twenty-one million, three hundred twenty-two thousand, two hundred twenty-eight".