21744193 has 2 divisors, whose sum is σ = 21744194. Its totient is φ = 21744192.

The previous prime is 21744181. The next prime is 21744209. The reversal of 21744193 is 39144712.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18948609 + 2795584 = 4353^2 + 1672^2 .

It is a cyclic number.

It is not a de Polignac number, because 21744193 - 2⁵ = 21744161 is a prime.

It is not a weakly prime, because it can be changed into another prime (21744143) 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 as a sum of consecutive naturals, namely, 10872096 + 10872097.

It is an arithmetic number, because the mean of its divisors is an integer number (10872097).

Almost surely, 2^21744193 is an apocalyptic number.

It is an amenable number.

21744193 is a deficient number, since it is larger than the sum of its proper divisors (1).

21744193 is an equidigital number, since it uses as much as digits as its factorization.

21744193 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6048, while the sum is 31.

The square root of 21744193 is about 4663.0669092347. The cubic root of 21744193 is about 279.1136641140.

The spelling of 21744193 in words is "twenty-one million, seven hundred forty-four thousand, one hundred ninety-three".