21818222 has 8 divisors (see below), whose sum is σ = 33051672. Its totient is φ = 10801000.

The previous prime is 21818221. The next prime is 21818227. The reversal of 21818222 is 22281812.

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

It is a super-2 number, since 2×21818222² = 952069622482568, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21818191 and 21818200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21818221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53804 + ... + 54207.

It is an arithmetic number, because the mean of its divisors is an integer number (4131459).

Almost surely, 2^21818222 is an apocalyptic number.

21818222 is a deficient number, since it is larger than the sum of its proper divisors (11233450).

21818222 is a wasteful number, since it uses less digits than its factorization.

21818222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108114.

The product of its digits is 1024, while the sum is 26.

The square root of 21818222 is about 4670.9979661738. The cubic root of 21818222 is about 279.4300566470.

The spelling of 21818222 in words is "twenty-one million, eight hundred eighteen thousand, two hundred twenty-two".