869820 has 96 divisors (see below), whose sum is σ = 2956800. Its totient is φ = 186624.

The previous prime is 869819. The next prime is 869849. The reversal of 869820 is 28968.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 7926 + ... + 8034.

It is an arithmetic number, because the mean of its divisors is an integer number (30800).

2⁸⁶⁹⁸²⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 869820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1478400).

869820 is an abundant number, since it is smaller than the sum of its proper divisors (2086980).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

869820 is a wasteful number, since it uses less digits than its factorization.

869820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147 (or 145 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 33.

The square root of 869820 is about 932.6414101894. The cubic root of 869820 is about 95.4574429135.

The spelling of 869820 in words is "eight hundred sixty-nine thousand, eight hundred twenty".