819855 has 16 divisors (see below), whose sum is σ = 1457760. Its totient is φ = 437184.

The previous prime is 819853. The next prime is 819899. The reversal of 819855 is 558918.

It is not a de Polignac number, because 819855 - 2¹ = 819853 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (819853) 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, 2902 + ... + 3171.

It is an arithmetic number, because the mean of its divisors is an integer number (91110).

2⁸¹⁹⁸⁵⁵ is an apocalyptic number.

819855 is a deficient number, since it is larger than the sum of its proper divisors (637905).

819855 is a wasteful number, since it uses less digits than its factorization.

819855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6087 (or 6081 counting only the distinct ones).

The product of its digits is 14400, while the sum is 36.

The square root of 819855 is about 905.4584474177. The cubic root of 819855 is about 93.5934988910.

The spelling of 819855 in words is "eight hundred nineteen thousand, eight hundred fifty-five".