728887777 has 4 divisors (see below), whose sum is σ = 728946196. Its totient is φ = 728829360.

The previous prime is 728887741. The next prime is 728887787. The reversal of 728887777 is 777788827.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 265820416 + 463067361 = 16304^2 + 21519^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-728887777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (728887787) 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 3 ways as a sum of consecutive naturals, for example, 2118 + ... + 38239.

It is an arithmetic number, because the mean of its divisors is an integer number (182236549).

Almost surely, 2^728887777 is an apocalyptic number.

It is an amenable number.

728887777 is a deficient number, since it is larger than the sum of its proper divisors (58419).

728887777 is a wasteful number, since it uses less digits than its factorization.

728887777 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58418.

The product of its digits is 17210368, while the sum is 61.

The square root of 728887777 is about 26997.9217163099. The cubic root of 728887777 is about 899.9538153255.

The spelling of 728887777 in words is "seven hundred twenty-eight million, eight hundred eighty-seven thousand, seven hundred seventy-seven".