811871 has 2 divisors, whose sum is σ = 811872. Its totient is φ = 811870.

The previous prime is 811861. The next prime is 811879. The reversal of 811871 is 178118.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-811871 is a prime.

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 811871.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (811879) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405935 + 405936.

It is an arithmetic number, because the mean of its divisors is an integer number (405936).

2⁸¹¹⁸⁷¹ is an apocalyptic number.

811871 is a deficient number, since it is larger than the sum of its proper divisors (1).

811871 is an equidigital number, since it uses as much as digits as its factorization.

811871 is an evil number, because the sum of its binary digits is even.

The product of its digits is 448, while the sum is 26.

The square root of 811871 is about 901.0388448896. The cubic root of 811871 is about 93.2886932218.

Adding to 811871 its reverse (178118), we get a palindrome (989989).

The spelling of 811871 in words is "eight hundred eleven thousand, eight hundred seventy-one".