2165220 has 72 divisors (see below), whose sum is σ = 6866496. Its totient is φ = 551232.

The previous prime is 2165213. The next prime is 2165231. The reversal of 2165220 is 225612.

2165220 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 2165193 and 2165202.

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, 3879 + ... + 4401.

It is an arithmetic number, because the mean of its divisors is an integer number (95368).

2^2165220 is an apocalyptic number.

2165220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2165220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3433248).

2165220 is an abundant number, since it is smaller than the sum of its proper divisors (4701276).

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

2165220 is a wasteful number, since it uses less digits than its factorization.

2165220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 561 (or 556 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 2165220 is about 1471.4686541004. The cubic root of 2165220 is about 129.3701286411.

The spelling of 2165220 in words is "two million, one hundred sixty-five thousand, two hundred twenty".