2081689 has 4 divisors (see below), whose sum is σ = 2085156. Its totient is φ = 2078224.

The previous prime is 2081687. The next prime is 2081719. The reversal of 2081689 is 9861802.

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 435600 + 1646089 = 660^2 + 1283^2 .

It is a cyclic number.

It is not a de Polignac number, because 2081689 - 2¹ = 2081687 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2081687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 574 + ... + 2119.

It is an arithmetic number, because the mean of its divisors is an integer number (521289).

2^2081689 is an apocalyptic number.

It is an amenable number.

2081689 is a deficient number, since it is larger than the sum of its proper divisors (3467).

2081689 is an equidigital number, since it uses as much as digits as its factorization.

2081689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3466.

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 2081689 is about 1442.8059467579. The cubic root of 2081689 is about 127.6846280708.

The spelling of 2081689 in words is "two million, eighty-one thousand, six hundred eighty-nine".