9725809 has 2 divisors, whose sum is σ = 9725810. Its totient is φ = 9725808.

The previous prime is 9725801. The next prime is 9725827. The reversal of 9725809 is 9085279.

9725809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8832784 + 893025 = 2972^2 + 945^2 .

It is a cyclic number.

It is not a de Polignac number, because 9725809 - 2³ = 9725801 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (9725801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4862904 + 4862905.

It is an arithmetic number, because the mean of its divisors is an integer number (4862905).

Almost surely, 2^9725809 is an apocalyptic number.

It is an amenable number.

9725809 is a deficient number, since it is larger than the sum of its proper divisors (1).

9725809 is an equidigital number, since it uses as much as digits as its factorization.

9725809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 45360, while the sum is 40.

The square root of 9725809 is about 3118.6229332832. The cubic root of 9725809 is about 213.4561041922.

The spelling of 9725809 in words is "nine million, seven hundred twenty-five thousand, eight hundred nine".