8491709 has 4 divisors (see below), whose sum is σ = 8507004. Its totient is φ = 8476416.

The previous prime is 8491697. The next prime is 8491711. The reversal of 8491709 is 9071948.

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 6175225 + 2316484 = 2485^2 + 1522^2 .

It is a cyclic number.

It is not a de Polignac number, because 8491709 - 2⁸ = 8491453 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8491409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6782 + ... + 7935.

It is an arithmetic number, because the mean of its divisors is an integer number (2126751).

Almost surely, 2^8491709 is an apocalyptic number.

It is an amenable number.

8491709 is a deficient number, since it is larger than the sum of its proper divisors (15295).

8491709 is a wasteful number, since it uses less digits than its factorization.

8491709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15294.

The product of its (nonzero) digits is 18144, while the sum is 38.

The square root of 8491709 is about 2914.0537057508. The cubic root of 8491709 is about 204.0163786030.

The spelling of 8491709 in words is "eight million, four hundred ninety-one thousand, seven hundred nine".