2165406 has 8 divisors (see below), whose sum is σ = 4330824. Its totient is φ = 721800.

The previous prime is 2165393. The next prime is 2165413. The reversal of 2165406 is 6045612.

It is a sphenic number, since it is the product of 3 distinct primes.

2165406 is an admirable number.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a d-powerful number, because it can be written as 2²¹ + 1 + 6⁴ + 5³ + 4⁸ + 0 + 6⁴ .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 180445 + ... + 180456.

It is an arithmetic number, because the mean of its divisors is an integer number (541353).

2^2165406 is an apocalyptic number.

2165406 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

2165406 is a wasteful number, since it uses less digits than its factorization.

2165406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 360906.

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 2165406 is about 1471.5318549049. The cubic root of 2165406 is about 129.3738329844.

The spelling of 2165406 in words is "two million, one hundred sixty-five thousand, four hundred six".