21123422 has 8 divisors (see below), whose sum is σ = 31723896. Its totient is φ = 10548792.

The previous prime is 21123391. The next prime is 21123457. The reversal of 21123422 is 22432112.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21123422.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4268 + ... + 7775.

It is an arithmetic number, because the mean of its divisors is an integer number (3965487).

Almost surely, 2^21123422 is an apocalyptic number.

21123422 is a deficient number, since it is larger than the sum of its proper divisors (10600474).

21123422 is a wasteful number, since it uses less digits than its factorization.

21123422 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12922.

The product of its digits is 192, while the sum is 17.

The square root of 21123422 is about 4596.0224107374. The cubic root of 21123422 is about 276.4318573515.

Adding to 21123422 its reverse (22432112), we get a palindrome (43555534).

The spelling of 21123422 in words is "twenty-one million, one hundred twenty-three thousand, four hundred twenty-two".