11988191 has 2 divisors, whose sum is σ = 11988192. Its totient is φ = 11988190.

The previous prime is 11988187. The next prime is 11988217. The reversal of 11988191 is 19188911.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 11988191 - 2² = 11988187 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11988121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5994095 + 5994096.

It is an arithmetic number, because the mean of its divisors is an integer number (5994096).

Almost surely, 2^11988191 is an apocalyptic number.

11988191 is a deficient number, since it is larger than the sum of its proper divisors (1).

11988191 is an equidigital number, since it uses as much as digits as its factorization.

11988191 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5184, while the sum is 38.

The square root of 11988191 is about 3462.3967132609. The cubic root of 11988191 is about 228.8677242486.

The spelling of 11988191 in words is "eleven million, nine hundred eighty-eight thousand, one hundred ninety-one".