855813 has 16 divisors (see below), whose sum is σ = 1322496. Its totient is φ = 482160.

The previous prime is 855787. The next prime is 855821. The reversal of 855813 is 318558.

It is a happy number.

It is not a de Polignac number, because 855813 - 2⁵ = 855781 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (855863) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1498 + ... + 1988.

It is an arithmetic number, because the mean of its divisors is an integer number (82656).

2⁸⁵⁵⁸¹³ is an apocalyptic number.

855813 is a gapful number since it is divisible by the number (83) formed by its first and last digit.

It is an amenable number.

855813 is a deficient number, since it is larger than the sum of its proper divisors (466683).

855813 is a wasteful number, since it uses less digits than its factorization.

855813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 584.

The product of its digits is 4800, while the sum is 30.

The square root of 855813 is about 925.1016160401. The cubic root of 855813 is about 94.9422733321.

The spelling of 855813 in words is "eight hundred fifty-five thousand, eight hundred thirteen".