19444561 has 2 divisors, whose sum is σ = 19444562. Its totient is φ = 19444560.

The previous prime is 19444559. The next prime is 19444577. The reversal of 19444561 is 16544491.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13950225 + 5494336 = 3735^2 + 2344^2 .

It is a cyclic number.

It is not a de Polignac number, because 19444561 - 2¹ = 19444559 is a prime.

Together with 19444559, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (19444501) 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, 9722280 + 9722281.

It is an arithmetic number, because the mean of its divisors is an integer number (9722281).

Almost surely, 2^19444561 is an apocalyptic number.

It is an amenable number.

19444561 is a deficient number, since it is larger than the sum of its proper divisors (1).

19444561 is an equidigital number, since it uses as much as digits as its factorization.

19444561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17280, while the sum is 34.

The square root of 19444561 is about 4409.5987345789. The cubic root of 19444561 is about 268.9053116337.

The spelling of 19444561 in words is "nineteen million, four hundred forty-four thousand, five hundred sixty-one".