21222316 has 24 divisors (see below), whose sum is σ = 40446000. Its totient is φ = 9705024.

The previous prime is 21222293. The next prime is 21222343. The reversal of 21222316 is 61322212.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a junction number, because it is equal to n+sod(n) for n = 21222293 and 21222302.

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 7 ways as a sum of consecutive naturals, for example, 2611 + ... + 7018.

It is an arithmetic number, because the mean of its divisors is an integer number (1685250).

Almost surely, 2^21222316 is an apocalyptic number.

It is an amenable number.

21222316 is a deficient number, since it is larger than the sum of its proper divisors (19223684).

21222316 is a wasteful number, since it uses less digits than its factorization.

21222316 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9681 (or 9679 counting only the distinct ones).

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

The square root of 21222316 is about 4606.7684986333. The cubic root of 21222316 is about 276.8625782924.

Adding to 21222316 its reverse (61322212), we get a palindrome (82544528).

The spelling of 21222316 in words is "twenty-one million, two hundred twenty-two thousand, three hundred sixteen".