728515609 has 2 divisors, whose sum is σ = 728515610. Its totient is φ = 728515608.

The previous prime is 728515597. The next prime is 728515649. The reversal of 728515609 is 906515827.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 440874009 + 287641600 = 20997^2 + 16960^2 .

It is a cyclic number.

It is not a de Polignac number, because 728515609 - 2⁵ = 728515577 is a prime.

It is not a weakly prime, because it can be changed into another prime (728515649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 364257804 + 364257805.

It is an arithmetic number, because the mean of its divisors is an integer number (364257805).

Almost surely, 2^728515609 is an apocalyptic number.

It is an amenable number.

728515609 is a deficient number, since it is larger than the sum of its proper divisors (1).

728515609 is an equidigital number, since it uses as much as digits as its factorization.

728515609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 151200, while the sum is 43.

The square root of 728515609 is about 26991.0283057167. The cubic root of 728515609 is about 899.8006179730.

The spelling of 728515609 in words is "seven hundred twenty-eight million, five hundred fifteen thousand, six hundred nine".