2165090 has 8 divisors (see below), whose sum is σ = 3897180. Its totient is φ = 866032.

The previous prime is 2165089. The next prime is 2165117. The reversal of 2165090 is 905612.

It can be written as a sum of positive squares in 2 ways, for example, as 1825201 + 339889 = 1351^2 + 583^2 .

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

It is a super-2 number, since 2×2165090² = 9375229416200, which contains 22 as substring.

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

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 108245 + ... + 108264.

2^2165090 is an apocalyptic number.

2165090 is a deficient number, since it is larger than the sum of its proper divisors (1732090).

2165090 is a wasteful number, since it uses less digits than its factorization.

2165090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 216516.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 2165090 is about 1471.4244798834. The cubic root of 2165090 is about 129.3675394579.

The spelling of 2165090 in words is "two million, one hundred sixty-five thousand, ninety".