19446378481 has 2 divisors, whose sum is σ = 19446378482. Its totient is φ = 19446378480.

The previous prime is 19446378449. The next prime is 19446378509. The reversal of 19446378481 is 18487364491.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18867494881 + 578883600 = 137359^2 + 24060^2 .

It is an emirp because it is prime and its reverse (18487364491) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19446378481 - 2⁵ = 19446378449 is a prime.

It is a super-2 number, since 2×19446378481² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (19446378181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9723189240 + 9723189241.

It is an arithmetic number, because the mean of its divisors is an integer number (9723189241).

Almost surely, 2^19446378481 is an apocalyptic number.

It is an amenable number.

19446378481 is a deficient number, since it is larger than the sum of its proper divisors (1).

19446378481 is an equidigital number, since it uses as much as digits as its factorization.

19446378481 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4644864, while the sum is 55.

The spelling of 19446378481 in words is "nineteen billion, four hundred forty-six million, three hundred seventy-eight thousand, four hundred eighty-one".