11563891 has 2 divisors, whose sum is σ = 11563892. Its totient is φ = 11563890.

The previous prime is 11563889. The next prime is 11563897. The reversal of 11563891 is 19836511.

11563891 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 11563891 - 2¹ = 11563889 is a prime.

Together with 11563889, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (11563897) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5781945 + 5781946.

It is an arithmetic number, because the mean of its divisors is an integer number (5781946).

Almost surely, 2^11563891 is an apocalyptic number.

11563891 is a deficient number, since it is larger than the sum of its proper divisors (1).

11563891 is an equidigital number, since it uses as much as digits as its factorization.

11563891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6480, while the sum is 34.

The square root of 11563891 is about 3400.5721577405. The cubic root of 11563891 is about 226.1351099072.

The spelling of 11563891 in words is "eleven million, five hundred sixty-three thousand, eight hundred ninety-one".