728003637128 has 8 divisors (see below), whose sum is σ = 1365006819630. Its totient is φ = 364001818560.

The previous prime is 728003637121. The next prime is 728003637133. The reversal of 728003637128 is 821736300827.

It can be written as a sum of positive squares in only one way, i.e., 694118927044 + 33884710084 = 833138^2 + 184078^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (728003637121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45500227313 + ... + 45500227328.

Almost surely, 2^728003637128 is an apocalyptic number.

It is an amenable number.

728003637128 is a deficient number, since it is larger than the sum of its proper divisors (637003182502).

728003637128 is a wasteful number, since it uses less digits than its factorization.

728003637128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91000454647 (or 91000454643 counting only the distinct ones).

The product of its (nonzero) digits is 677376, while the sum is 47.

The spelling of 728003637128 in words is "seven hundred twenty-eight billion, three million, six hundred thirty-seven thousand, one hundred twenty-eight".