728816591 has 4 divisors (see below), whose sum is σ = 732843384. Its totient is φ = 724789800.

The previous prime is 728816563. The next prime is 728816623. The reversal of 728816591 is 195618827.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 195618827 = 181 ⋅1080767.

It is a cyclic number.

It is not a de Polignac number, because 728816591 - 2⁶ = 728816527 is a prime.

It is a super-2 number, since 2×728816591² = 1062347246633722562, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (728818591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2013125 + ... + 2013486.

It is an arithmetic number, because the mean of its divisors is an integer number (183210846).

Almost surely, 2^728816591 is an apocalyptic number.

728816591 is a deficient number, since it is larger than the sum of its proper divisors (4026793).

728816591 is a wasteful number, since it uses less digits than its factorization.

728816591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4026792.

The product of its digits is 241920, while the sum is 47.

The square root of 728816591 is about 26996.6033233813. The cubic root of 728816591 is about 899.9245167146.

The spelling of 728816591 in words is "seven hundred twenty-eight million, eight hundred sixteen thousand, five hundred ninety-one".