862891 has 4 divisors (see below), whose sum is σ = 900432. Its totient is φ = 825352.

The previous prime is 862879. The next prime is 862907. The reversal of 862891 is 198268.

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 862891 - 2¹¹ = 860843 is a prime.

It is a Duffinian number.

862891 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (862811) 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, 18736 + ... + 18781.

It is an arithmetic number, because the mean of its divisors is an integer number (225108).

2⁸⁶²⁸⁹¹ is an apocalyptic number.

862891 is the 588-th centered pentagonal number.

862891 is a deficient number, since it is larger than the sum of its proper divisors (37541).

862891 is a wasteful number, since it uses less digits than its factorization.

862891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37540.

The product of its digits is 6912, while the sum is 34.

The square root of 862891 is about 928.9192645219. The cubic root of 862891 is about 95.2032950275.

The spelling of 862891 in words is "eight hundred sixty-two thousand, eight hundred ninety-one".