11891387 has 2 divisors, whose sum is σ = 11891388. Its totient is φ = 11891386.

The previous prime is 11891371. The next prime is 11891389. The reversal of 11891387 is 78319811.

11891387 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 11891387 - 2⁴ = 11891371 is a prime.

Together with 11891389, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11891387.

It is not a weakly prime, because it can be changed into another prime (11891389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5945693 + 5945694.

It is an arithmetic number, because the mean of its divisors is an integer number (5945694).

Almost surely, 2^11891387 is an apocalyptic number.

11891387 is a deficient number, since it is larger than the sum of its proper divisors (1).

11891387 is an equidigital number, since it uses as much as digits as its factorization.

11891387 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 38.

The square root of 11891387 is about 3448.3890441770. The cubic root of 11891387 is about 228.2500270923.

The spelling of 11891387 in words is "eleven million, eight hundred ninety-one thousand, three hundred eighty-seven".