1728731443009 has 2 divisors, whose sum is σ = 1728731443010. Its totient is φ = 1728731443008.

The previous prime is 1728731442953. The next prime is 1728731443013. The reversal of 1728731443009 is 9003441378271.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1573281033025 + 155450409984 = 1254305^2 + 394272^2 .

It is a cyclic number.

It is not a de Polignac number, because 1728731443009 - 2⁹ = 1728731442497 is a prime.

It is not a weakly prime, because it can be changed into another prime (1728731443409) 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, 864365721504 + 864365721505.

It is an arithmetic number, because the mean of its divisors is an integer number (864365721505).

Almost surely, 2^{1728731443009} is an apocalyptic number.

It is an amenable number.

1728731443009 is a deficient number, since it is larger than the sum of its proper divisors (1).

1728731443009 is an equidigital number, since it uses as much as digits as its factorization.

1728731443009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1016064, while the sum is 49.

The spelling of 1728731443009 in words is "one trillion, seven hundred twenty-eight billion, seven hundred thirty-one million, four hundred forty-three thousand, nine".