728563394 has 12 divisors (see below), whose sum is σ = 1183377186. Its totient is φ = 336259872.

The previous prime is 728563361. The next prime is 728563421. The reversal of 728563394 is 493365827.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 381225625 + 347337769 = 19525^2 + 18637^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1077419 + ... + 1078094.

Almost surely, 2^728563394 is an apocalyptic number.

728563394 is a deficient number, since it is larger than the sum of its proper divisors (454813792).

728563394 is a wasteful number, since it uses less digits than its factorization.

728563394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2155541 (or 2155528 counting only the distinct ones).

The product of its digits is 1088640, while the sum is 47.

The square root of 728563394 is about 26991.9134927482. The cubic root of 728563394 is about 899.8202908676.

The spelling of 728563394 in words is "seven hundred twenty-eight million, five hundred sixty-three thousand, three hundred ninety-four".