2163685 has 4 divisors (see below), whose sum is σ = 2596428. Its totient is φ = 1730944.

The previous prime is 2163677. The next prime is 2163691. The reversal of 2163685 is 5863612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1595169 + 568516 = 1263^2 + 754^2 .

It is a cyclic number.

It is not a de Polignac number, because 2163685 - 2³ = 2163677 is a prime.

It is a Smith number, since the sum of its digits (31) 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 2¹⁷ + 1 + 6² + 3³ + 6⁶ + 8⁵ + 5⁹ .

It is a Duffinian number.

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, 216364 + ... + 216373.

It is an arithmetic number, because the mean of its divisors is an integer number (649107).

2^2163685 is an apocalyptic number.

It is an amenable number.

2163685 is a deficient number, since it is larger than the sum of its proper divisors (432743).

2163685 is an equidigital number, since it uses as much as digits as its factorization.

2163685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432742.

The product of its digits is 8640, while the sum is 31.

The square root of 2163685 is about 1470.9469738913. The cubic root of 2163685 is about 129.3395497478.

The spelling of 2163685 in words is "two million, one hundred sixty-three thousand, six hundred eighty-five".