2099729 has 4 divisors (see below), whose sum is σ = 2102820. Its totient is φ = 2096640.

The previous prime is 2099717. The next prime is 2099731. The reversal of 2099729 is 9279902.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 719104 + 1380625 = 848^2 + 1175^2 .

It is a cyclic number.

It is not a de Polignac number, because 2099729 - 2²⁰ = 1051153 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2099692 and 2099701.

It is not an unprimeable number, because it can be changed into a prime (2099749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32 + ... + 2049.

It is an arithmetic number, because the mean of its divisors is an integer number (525705).

2^2099729 is an apocalyptic number.

It is an amenable number.

2099729 is a deficient number, since it is larger than the sum of its proper divisors (3091).

2099729 is a wasteful number, since it uses less digits than its factorization.

2099729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3090.

The product of its (nonzero) digits is 20412, while the sum is 38.

The square root of 2099729 is about 1449.0441677188. The cubic root of 2099729 is about 128.0524077387.

The spelling of 2099729 in words is "two million, ninety-nine thousand, seven hundred twenty-nine".