728731668 has 24 divisors (see below), whose sum is σ = 1943284672. Its totient is φ = 208209024.

The previous prime is 728731657. The next prime is 728731669. The reversal of 728731668 is 866137827.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (728731669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4337605 + ... + 4337772.

Almost surely, 2^728731668 is an apocalyptic number.

It is an amenable number.

728731668 is an abundant number, since it is smaller than the sum of its proper divisors (1214553004).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

728731668 is a wasteful number, since it uses less digits than its factorization.

728731668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8675391 (or 8675389 counting only the distinct ones).

The product of its digits is 677376, while the sum is 48.

The square root of 728731668 is about 26995.0304315442. The cubic root of 728731668 is about 899.8895617574.

The spelling of 728731668 in words is "seven hundred twenty-eight million, seven hundred thirty-one thousand, six hundred sixty-eight".