11555712181 has 8 divisors (see below), whose sum is σ = 12473359640. Its totient is φ = 10642171392.

The previous prime is 11555712169. The next prime is 11555712227. The reversal of 11555712181 is 18121755511.

It can be written as a sum of positive squares in 4 ways, for example, as 550653156 + 11005059025 = 23466^2 + 104905^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 11555712181 - 2¹³ = 11555703989 is a prime.

It is a super-2 number, since 2×11555712181² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11555712181.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11555712881) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1020816 + ... + 1032073.

It is an arithmetic number, because the mean of its divisors is an integer number (1559169955).

Almost surely, 2^11555712181 is an apocalyptic number.

It is an amenable number.

11555712181 is a deficient number, since it is larger than the sum of its proper divisors (917647459).

11555712181 is a wasteful number, since it uses less digits than its factorization.

11555712181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2053335.

The product of its digits is 14000, while the sum is 37.

The spelling of 11555712181 in words is "eleven billion, five hundred fifty-five million, seven hundred twelve thousand, one hundred eighty-one".