19643441 has 2 divisors, whose sum is σ = 19643442. Its totient is φ = 19643440.

The previous prime is 19643431. The next prime is 19643453. The reversal of 19643441 is 14434691.

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., 17305600 + 2337841 = 4160^2 + 1529^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19643441 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 19643398 and 19643407.

It is not a weakly prime, because it can be changed into another prime (19643431) 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 as a sum of consecutive naturals, namely, 9821720 + 9821721.

It is an arithmetic number, because the mean of its divisors is an integer number (9821721).

Almost surely, 2^19643441 is an apocalyptic number.

It is an amenable number.

19643441 is a deficient number, since it is larger than the sum of its proper divisors (1).

19643441 is an equidigital number, since it uses as much as digits as its factorization.

19643441 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10368, while the sum is 32.

The square root of 19643441 is about 4432.0921696192. The cubic root of 19643441 is about 269.8189961976.

The spelling of 19643441 in words is "nineteen million, six hundred forty-three thousand, four hundred forty-one".