810881 has 2 divisors, whose sum is σ = 810882. Its totient is φ = 810880.

The previous prime is 810871. The next prime is 810893. The reversal of 810881 is 188018.

810881 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 774400 + 36481 = 880^2 + 191^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-810881 is a prime.

It is a super-2 number, since 2×810881² = 1315055992322, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 810881.

It is not a weakly prime, because it can be changed into another prime (810871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405440 + 405441.

It is an arithmetic number, because the mean of its divisors is an integer number (405441).

2⁸¹⁰⁸⁸¹ is an apocalyptic number.

It is an amenable number.

810881 is a deficient number, since it is larger than the sum of its proper divisors (1).

810881 is an equidigital number, since it uses as much as digits as its factorization.

810881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 512, while the sum is 26.

The square root of 810881 is about 900.4893114302. The cubic root of 810881 is about 93.2507588819.

Adding to 810881 its reverse (188018), we get a palindrome (998899).

The spelling of 810881 in words is "eight hundred ten thousand, eight hundred eighty-one".