728881 has 2 divisors, whose sum is σ = 728882. Its totient is φ = 728880.

The previous prime is 728873. The next prime is 728891. The reversal of 728881 is 188827.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 512656 + 216225 = 716^2 + 465^2 .

It is an emirp because it is prime and its reverse (188827) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 728881 - 2³ = 728873 is a prime.

It is a super-2 number, since 2×728881² = 1062535024322, which contains 22 as substring.

728881 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (728831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 364440 + 364441.

It is an arithmetic number, because the mean of its divisors is an integer number (364441).

2⁷²⁸⁸⁸¹ is an apocalyptic number.

It is an amenable number.

728881 is a deficient number, since it is larger than the sum of its proper divisors (1).

728881 is an equidigital number, since it uses as much as digits as its factorization.

728881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7168, while the sum is 34.

The square root of 728881 is about 853.7452781714. The cubic root of 728881 is about 89.9951026142.

The spelling of 728881 in words is "seven hundred twenty-eight thousand, eight hundred eighty-one".