11491559 has 4 divisors (see below), whose sum is σ = 11991216. Its totient is φ = 10991904.

The previous prime is 11491531. The next prime is 11491573. The reversal of 11491559 is 95519411.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 95519411 = 13 ⋅7347647.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11491559 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11491159) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 249794 + ... + 249839.

It is an arithmetic number, because the mean of its divisors is an integer number (2997804).

Almost surely, 2^11491559 is an apocalyptic number.

11491559 is a deficient number, since it is larger than the sum of its proper divisors (499657).

11491559 is an equidigital number, since it uses as much as digits as its factorization.

11491559 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 499656.

The product of its digits is 8100, while the sum is 35.

The square root of 11491559 is about 3389.9202055506. The cubic root of 11491559 is about 225.6626326170.

The spelling of 11491559 in words is "eleven million, four hundred ninety-one thousand, five hundred fifty-nine".