21354443 has 12 divisors (see below), whose sum is σ = 24233664. Its totient is φ = 18783600.

The previous prime is 21354433. The next prime is 21354449. The reversal of 21354443 is 34445312.

It is not a de Polignac number, because 21354443 - 2¹⁰ = 21353419 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21354449) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 905 + ... + 6597.

It is an arithmetic number, because the mean of its divisors is an integer number (2019472).

Almost surely, 2^21354443 is an apocalyptic number.

21354443 is a deficient number, since it is larger than the sum of its proper divisors (2879221).

21354443 is a wasteful number, since it uses less digits than its factorization.

21354443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5746 (or 5735 counting only the distinct ones).

The product of its digits is 5760, while the sum is 26.

The square root of 21354443 is about 4621.0867769389. The cubic root of 21354443 is about 277.4359584922.

Adding to 21354443 its reverse (34445312), we get a palindrome (55799755).

The spelling of 21354443 in words is "twenty-one million, three hundred fifty-four thousand, four hundred forty-three".