728003657 has 4 divisors (see below), whose sum is σ = 735211716. Its totient is φ = 720795600.

The previous prime is 728003641. The next prime is 728003687. The reversal of 728003657 is 756300827.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 756300827 = 101 ⋅7488127.

It can be written as a sum of positive squares in 2 ways, for example, as 382750096 + 345253561 = 19564^2 + 18581^2 .

It is a cyclic number.

It is not a de Polignac number, because 728003657 - 2⁴ = 728003641 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 728003657.

It is not an unprimeable number, because it can be changed into a prime (728003687) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3603878 + ... + 3604079.

It is an arithmetic number, because the mean of its divisors is an integer number (183802929).

Almost surely, 2^728003657 is an apocalyptic number.

It is an amenable number.

728003657 is a deficient number, since it is larger than the sum of its proper divisors (7208059).

728003657 is a wasteful number, since it uses less digits than its factorization.

728003657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7208058.

The product of its (nonzero) digits is 70560, while the sum is 38.

The square root of 728003657 is about 26981.5428950978. The cubic root of 728003657 is about 899.5897953687.

The spelling of 728003657 in words is "seven hundred twenty-eight million, three thousand, six hundred fifty-seven".