9709891 has 2 divisors, whose sum is σ = 9709892. Its totient is φ = 9709890.

The previous prime is 9709859. The next prime is 9709897. The reversal of 9709891 is 1989079.

9709891 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 9709891 - 2⁵ = 9709859 is a prime.

It is not a weakly prime, because it can be changed into another prime (9709897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4854945 + 4854946.

It is an arithmetic number, because the mean of its divisors is an integer number (4854946).

Almost surely, 2^9709891 is an apocalyptic number.

9709891 is a deficient number, since it is larger than the sum of its proper divisors (1).

9709891 is an equidigital number, since it uses as much as digits as its factorization.

9709891 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40824, while the sum is 43.

The square root of 9709891 is about 3116.0698002452. The cubic root of 9709891 is about 213.3395877615.

The spelling of 9709891 in words is "nine million, seven hundred nine thousand, eight hundred ninety-one".