19447 has 2 divisors, whose sum is σ = 19448. Its totient is φ = 19446.

The previous prime is 19441. The next prime is 19457. The reversal of 19447 is 74491.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19447 - 2⁷ = 19319 is a prime.

It is a plaindrome in base 11.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19441) 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, 9723 + 9724.

It is an arithmetic number, because the mean of its divisors is an integer number (9724).

2¹⁹⁴⁴⁷ is an apocalyptic number.

19447 is a deficient number, since it is larger than the sum of its proper divisors (1).

19447 is an equidigital number, since it uses as much as digits as its factorization.

19447 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1008, while the sum is 25.

The square root of 19447 is about 139.4525008740. The cubic root of 19447 is about 26.8916554411.

The spelling of 19447 in words is "nineteen thousand, four hundred forty-seven".