11689991 has 2 divisors, whose sum is σ = 11689992. Its totient is φ = 11689990.

The previous prime is 11689973. The next prime is 11690011. The reversal of 11689991 is 19998611.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 11689991 - 2²² = 7495687 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11689901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5844995 + 5844996.

It is an arithmetic number, because the mean of its divisors is an integer number (5844996).

Almost surely, 2^11689991 is an apocalyptic number.

11689991 is a deficient number, since it is larger than the sum of its proper divisors (1).

11689991 is an equidigital number, since it uses as much as digits as its factorization.

11689991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34992, while the sum is 44.

The square root of 11689991 is about 3419.0628833059. The cubic root of 11689991 is about 226.9541136461.

The spelling of 11689991 in words is "eleven million, six hundred eighty-nine thousand, nine hundred ninety-one".