11185578687881 has 4 divisors (see below), whose sum is σ = 12046007817732. Its totient is φ = 10325149558032.

The previous prime is 11185578687859. The next prime is 11185578687893. The reversal of 11185578687881 is 18878687558111.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2877464223481 + 8308114464400 = 1696309^2 + 2882380^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11185578687881 is a prime.

It is a super-2 number, since 2×11185578687881² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11185578687799 and 11185578687808.

It is not an unprimeable number, because it can be changed into a prime (11185578987881) 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, 430214564906 + ... + 430214564931.

It is an arithmetic number, because the mean of its divisors is an integer number (3011501954433).

Almost surely, 2^{11185578687881} is an apocalyptic number.

It is an amenable number.

11185578687881 is a deficient number, since it is larger than the sum of its proper divisors (860429129851).

11185578687881 is an equidigital number, since it uses as much as digits as its factorization.

11185578687881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 860429129850.

The product of its digits is 240844800, while the sum is 74.

The spelling of 11185578687881 in words is "eleven trillion, one hundred eighty-five billion, five hundred seventy-eight million, six hundred eighty-seven thousand, eight hundred eighty-one".