11887204991 has 4 divisors (see below), whose sum is σ = 11898042192. Its totient is φ = 11876367792.

The previous prime is 11887204981. The next prime is 11887204997. The reversal of 11887204991 is 19940278811.

It is a happy number.

11887204991 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, and also an emirpimes, since its reverse is a distinct semiprime: 19940278811 = 1559 ⋅12790429.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11887204991 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 (11887204997) 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 in 3 ways as a sum of consecutive naturals, for example, 5416955 + ... + 5419148.

It is an arithmetic number, because the mean of its divisors is an integer number (2974510548).

Almost surely, 2^11887204991 is an apocalyptic number.

11887204991 is a deficient number, since it is larger than the sum of its proper divisors (10837201).

11887204991 is a wasteful number, since it uses less digits than its factorization.

11887204991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10837200.

The product of its (nonzero) digits is 290304, while the sum is 50.

The spelling of 11887204991 in words is "eleven billion, eight hundred eighty-seven million, two hundred four thousand, nine hundred ninety-one".