845820 has 72 divisors (see below), whose sum is σ = 2655744. Its totient is φ = 217728.

The previous prime is 845809. The next prime is 845833. The reversal of 845820 is 28548.

845820 is a `hidden beast` number, since 84 + 582 + 0 = 666.

It is a super-2 number, since 2×845820² = 1430822944800, which contains 22 as substring.

It is a zygodrome in base 2.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6597 + ... + 6723.

2⁸⁴⁵⁸²⁰ 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 845820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1327872).

845820 is an abundant number, since it is smaller than the sum of its proper divisors (1809924).

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

845820 is a wasteful number, since it uses less digits than its factorization.

845820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179 (or 174 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 27.

The square root of 845820 is about 919.6847285891. The cubic root of 845820 is about 94.5712907919.

The spelling of 845820 in words is "eight hundred forty-five thousand, eight hundred twenty".