816811 has 2 divisors, whose sum is σ = 816812. Its totient is φ = 816810.

The previous prime is 816779. The next prime is 816817. The reversal of 816811 is 118618.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 816811 - 2⁵ = 816779 is a prime.

816811 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (816817) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 408405 + 408406.

It is an arithmetic number, because the mean of its divisors is an integer number (408406).

2⁸¹⁶⁸¹¹ is an apocalyptic number.

816811 is a deficient number, since it is larger than the sum of its proper divisors (1).

816811 is an equidigital number, since it uses as much as digits as its factorization.

816811 is an evil number, because the sum of its binary digits is even.

The product of its digits is 384, while the sum is 25.

The square root of 816811 is about 903.7759678150. The cubic root of 816811 is about 93.4775223118.

The spelling of 816811 in words is "eight hundred sixteen thousand, eight hundred eleven".