2099665 has 4 divisors (see below), whose sum is σ = 2519604. Its totient is φ = 1679728.

The previous prime is 2099659. The next prime is 2099677. The reversal of 2099665 is 5669902.

It is a happy number.

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 744769 + 1354896 = 863^2 + 1164^2 .

It is a cyclic number.

It is not a de Polignac number, because 2099665 - 2¹¹ = 2097617 is a prime.

It is a super-2 number, since 2×2099665² = 8817186224450, which contains 22 as substring.

It is a Duffinian 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, 209962 + ... + 209971.

It is an arithmetic number, because the mean of its divisors is an integer number (629901).

2^2099665 is an apocalyptic number.

It is an amenable number.

2099665 is a deficient number, since it is larger than the sum of its proper divisors (419939).

2099665 is an equidigital number, since it uses as much as digits as its factorization.

2099665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 419938.

The product of its (nonzero) digits is 29160, while the sum is 37.

The square root of 2099665 is about 1449.0220840277. The cubic root of 2099665 is about 128.0511067077.

The spelling of 2099665 in words is "two million, ninety-nine thousand, six hundred sixty-five".