11566539387 has 24 divisors (see below), whose sum is σ = 18011177184. Its totient is φ = 7110440064.

The previous prime is 11566539359. The next prime is 11566539403. The reversal of 11566539387 is 78393566511.

11566539387 is a `hidden beast` number, since 1 + 15 + 66 + 539 + 38 + 7 = 666.

It is not a de Polignac number, because 11566539387 - 2²² = 11562345083 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11566539317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 62023 + ... + 164255.

It is an arithmetic number, because the mean of its divisors is an integer number (750465716).

Almost surely, 2^11566539387 is an apocalyptic number.

11566539387 is a deficient number, since it is larger than the sum of its proper divisors (6444637797).

11566539387 is a wasteful number, since it uses less digits than its factorization.

11566539387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103219 (or 103216 counting only the distinct ones).

The product of its digits is 4082400, while the sum is 54.

The spelling of 11566539387 in words is "eleven billion, five hundred sixty-six million, five hundred thirty-nine thousand, three hundred eighty-seven".