728639444 has 24 divisors (see below), whose sum is σ = 1381347240. Its totient is φ = 336291072.

The previous prime is 728639437. The next prime is 728639447. The reversal of 728639444 is 444936827.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 326235844 + 402403600 = 18062^2 + 20060^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (728639447) 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 in 7 ways as a sum of consecutive naturals, for example, 32669 + ... + 50244.

It is an arithmetic number, because the mean of its divisors is an integer number (57556135).

Almost surely, 2^728639444 is an apocalyptic number.

It is an amenable number.

728639444 is a deficient number, since it is larger than the sum of its proper divisors (652707796).

728639444 is a wasteful number, since it uses less digits than its factorization.

728639444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82956 (or 82928 counting only the distinct ones).

The product of its digits is 1161216, while the sum is 47.

The square root of 728639444 is about 26993.3222112433. The cubic root of 728639444 is about 899.8515985766.

The spelling of 728639444 in words is "seven hundred twenty-eight million, six hundred thirty-nine thousand, four hundred forty-four".