21222634 has 4 divisors (see below), whose sum is σ = 31833954. Its totient is φ = 10611316.

The previous prime is 21222611. The next prime is 21222653. The reversal of 21222634 is 43622212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 11594025 + 9628609 = 3405^2 + 3103^2 .

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax 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 as a sum of consecutive naturals, namely, 5305657 + ... + 5305660.

Almost surely, 2^21222634 is an apocalyptic number.

21222634 is a deficient number, since it is larger than the sum of its proper divisors (10611320).

21222634 is a wasteful number, since it uses less digits than its factorization.

21222634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10611319.

The product of its digits is 1152, while the sum is 22.

The square root of 21222634 is about 4606.8030129364. The cubic root of 21222634 is about 276.8639611427.

Adding to 21222634 its reverse (43622212), we get a palindrome (64844846).

The spelling of 21222634 in words is "twenty-one million, two hundred twenty-two thousand, six hundred thirty-four".