728698309 has 2 divisors, whose sum is σ = 728698310. Its totient is φ = 728698308.

The previous prime is 728698301. The next prime is 728698379. The reversal of 728698309 is 903896827.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 590635809 + 138062500 = 24303^2 + 11750^2 .

It is a cyclic number.

It is not a de Polignac number, because 728698309 - 2³ = 728698301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (728698301) 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, 364349154 + 364349155.

It is an arithmetic number, because the mean of its divisors is an integer number (364349155).

Almost surely, 2^728698309 is an apocalyptic number.

It is an amenable number.

728698309 is a deficient number, since it is larger than the sum of its proper divisors (1).

728698309 is an equidigital number, since it uses as much as digits as its factorization.

728698309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1306368, while the sum is 52.

The square root of 728698309 is about 26994.4125514892. The cubic root of 728698309 is about 899.8758301946.

The spelling of 728698309 in words is "seven hundred twenty-eight million, six hundred ninety-eight thousand, three hundred nine".