21044593 has 4 divisors (see below), whose sum is σ = 21128688. Its totient is φ = 20960500.

The previous prime is 21044581. The next prime is 21044627. The reversal of 21044593 is 39544012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21044593 - 2⁹ = 21044081 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21044293) by changing a digit.

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, 41671 + ... + 42172.

It is an arithmetic number, because the mean of its divisors is an integer number (5282172).

Almost surely, 2^21044593 is an apocalyptic number.

It is an amenable number.

21044593 is a deficient number, since it is larger than the sum of its proper divisors (84095).

21044593 is an equidigital number, since it uses as much as digits as its factorization.

21044593 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84094.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 21044593 is about 4587.4386099435. The cubic root of 21044593 is about 276.0875632342.

The spelling of 21044593 in words is "twenty-one million, forty-four thousand, five hundred ninety-three".