1728561307813 has 2 divisors, whose sum is σ = 1728561307814. Its totient is φ = 1728561307812.

The previous prime is 1728561307807. The next prime is 1728561307871. The reversal of 1728561307813 is 3187031658271.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1698244229889 + 30317077924 = 1303167^2 + 174118^2 .

It is a cyclic number.

It is not a de Polignac number, because 1728561307813 - 2²¹ = 1728559210661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1728561307873) 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, 864280653906 + 864280653907.

It is an arithmetic number, because the mean of its divisors is an integer number (864280653907).

Almost surely, 2^{1728561307813} is an apocalyptic number.

It is an amenable number.

1728561307813 is a deficient number, since it is larger than the sum of its proper divisors (1).

1728561307813 is an equidigital number, since it uses as much as digits as its factorization.

1728561307813 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1693440, while the sum is 52.

The spelling of 1728561307813 in words is "one trillion, seven hundred twenty-eight billion, five hundred sixty-one million, three hundred seven thousand, eight hundred thirteen".