21422443 has 8 divisors (see below), whose sum is σ = 25771520. Its totient is φ = 17395560.

The previous prime is 21422419. The next prime is 21422449. The reversal of 21422443 is 34422412.

It is a happy number.

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

It is not a de Polignac number, because 21422443 - 2⁵ = 21422411 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21422449) 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 in 7 ways as a sum of consecutive naturals, for example, 80403 + ... + 80668.

It is an arithmetic number, because the mean of its divisors is an integer number (3221440).

Almost surely, 2^21422443 is an apocalyptic number.

21422443 is a deficient number, since it is larger than the sum of its proper divisors (4349077).

21422443 is a wasteful number, since it uses less digits than its factorization.

21422443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161097.

The product of its digits is 1536, while the sum is 22.

The square root of 21422443 is about 4628.4385055870. The cubic root of 21422443 is about 277.7301307728.

Adding to 21422443 its reverse (34422412), we get a palindrome (55844855).

The spelling of 21422443 in words is "twenty-one million, four hundred twenty-two thousand, four hundred forty-three".