11871261557 has 16 divisors (see below), whose sum is σ = 12314021760. Its totient is φ = 11438481600.

The previous prime is 11871261539. The next prime is 11871261581. The reversal of 11871261557 is 75516217811.

11871261557 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 11871261557 - 2¹⁴ = 11871245173 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 (11871261257) 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 15 ways as a sum of consecutive naturals, for example, 716507 + ... + 732887.

It is an arithmetic number, because the mean of its divisors is an integer number (769626360).

Almost surely, 2^11871261557 is an apocalyptic number.

It is an amenable number.

11871261557 is a deficient number, since it is larger than the sum of its proper divisors (442760203).

11871261557 is a wasteful number, since it uses less digits than its factorization.

11871261557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16684.

The product of its digits is 117600, while the sum is 44.

The spelling of 11871261557 in words is "eleven billion, eight hundred seventy-one million, two hundred sixty-one thousand, five hundred fifty-seven".