811867 has 4 divisors (see below), whose sum is σ = 927856. Its totient is φ = 695880.

The previous prime is 811861. The next prime is 811871. The reversal of 811867 is 768118.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 811867 - 2¹⁹ = 287579 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (811861) 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 in 3 ways as a sum of consecutive naturals, for example, 57984 + ... + 57997.

It is an arithmetic number, because the mean of its divisors is an integer number (231964).

2⁸¹¹⁸⁶⁷ is an apocalyptic number.

811867 is a deficient number, since it is larger than the sum of its proper divisors (115989).

811867 is a wasteful number, since it uses less digits than its factorization.

811867 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115988.

The product of its digits is 2688, while the sum is 31.

The square root of 811867 is about 901.0366252267. The cubic root of 811867 is about 93.2885400138.

The spelling of 811867 in words is "eight hundred eleven thousand, eight hundred sixty-seven".