9161891 has 2 divisors, whose sum is σ = 9161892. Its totient is φ = 9161890.

The previous prime is 9161869. The next prime is 9161897. The reversal of 9161891 is 1981619.

9161891 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is an emirp because it is prime and its reverse (1981619) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9161891 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (9161897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4580945 + 4580946.

It is an arithmetic number, because the mean of its divisors is an integer number (4580946).

Almost surely, 2^9161891 is an apocalyptic number.

9161891 is a deficient number, since it is larger than the sum of its proper divisors (1).

9161891 is an equidigital number, since it uses as much as digits as its factorization.

9161891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3888, while the sum is 35.

The square root of 9161891 is about 3026.8615759562. The cubic root of 9161891 is about 209.2481884806.

The spelling of 9161891 in words is "nine million, one hundred sixty-one thousand, eight hundred ninety-one".