728366081 has 4 divisors (see below), whose sum is σ = 728438832. Its totient is φ = 728293332.

The previous prime is 728366077. The next prime is 728366131. The reversal of 728366081 is 180663827.

It is a happy number.

728366081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 180663827 = 23 ⋅7854949.

It is a cyclic number.

It is not a de Polignac number, because 728366081 - 2² = 728366077 is a prime.

It is a super-2 number, since 2×728366081² = 1061034295902597122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (728366011) 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, 18395 + ... + 42368.

It is an arithmetic number, because the mean of its divisors is an integer number (182109708).

Almost surely, 2^728366081 is an apocalyptic number.

It is an amenable number.

728366081 is a deficient number, since it is larger than the sum of its proper divisors (72751).

728366081 is a wasteful number, since it uses less digits than its factorization.

728366081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72750.

The product of its (nonzero) digits is 96768, while the sum is 41.

The square root of 728366081 is about 26988.2582061162. The cubic root of 728366081 is about 899.7390523312.

The spelling of 728366081 in words is "seven hundred twenty-eight million, three hundred sixty-six thousand, eighty-one".