2165670 has 64 divisors (see below), whose sum is σ = 6229440. Its totient is φ = 532224.

The previous prime is 2165663. The next prime is 2165671. The reversal of 2165670 is 765612.

2165670 is a `hidden beast` number, since 2 + 1 + 656 + 7 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2165671) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3202 + ... + 3818.

It is an arithmetic number, because the mean of its divisors is an integer number (97335).

2^2165670 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2165670, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3114720).

2165670 is an abundant number, since it is smaller than the sum of its proper divisors (4063770).

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

2165670 is a wasteful number, since it uses less digits than its factorization.

2165670 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 646 (or 640 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The square root of 2165670 is about 1471.6215546125. The cubic root of 2165670 is about 129.3790903979.

It can be divided in two parts, 216 and 5670, that added together give a triangular number (5886 = T₁₀₈).

The spelling of 2165670 in words is "two million, one hundred sixty-five thousand, six hundred seventy".