11549991 has 4 divisors (see below), whose sum is σ = 15399992. Its totient is φ = 7699992.

The previous prime is 11549983. The next prime is 11550029. The reversal of 11549991 is 19994511.

11549991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 11549991 - 2³ = 11549983 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 (11549971) 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, 1924996 + ... + 1925001.

It is an arithmetic number, because the mean of its divisors is an integer number (3849998).

Almost surely, 2^11549991 is an apocalyptic number.

11549991 is a deficient number, since it is larger than the sum of its proper divisors (3850001).

11549991 is an equidigital number, since it uses as much as digits as its factorization.

11549991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3850000.

The product of its digits is 14580, while the sum is 39.

The square root of 11549991 is about 3398.5277694908. The cubic root of 11549991 is about 226.0444674555.

The spelling of 11549991 in words is "eleven million, five hundred forty-nine thousand, nine hundred ninety-one".