1191191689 has 8 divisors (see below), whose sum is σ = 1245150720. Its totient is φ = 1137413376.

The previous prime is 1191191671. The next prime is 1191191693. The reversal of 1191191689 is 9861911911.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1191191689 - 2⁵ = 1191191657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1191191629) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31609 + ... + 58150.

It is an arithmetic number, because the mean of its divisors is an integer number (155643840).

Almost surely, 2^1191191689 is an apocalyptic number.

It is an amenable number.

1191191689 is a deficient number, since it is larger than the sum of its proper divisors (53959031).

1191191689 is an equidigital number, since it uses as much as digits as its factorization.

1191191689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90359.

The product of its digits is 34992, while the sum is 46.

The square root of 1191191689 is about 34513.6449683310. The cubic root of 1191191689 is about 1060.0521182989.

The spelling of 1191191689 in words is "one billion, one hundred ninety-one million, one hundred ninety-one thousand, six hundred eighty-nine".