11661181 has 8 divisors (see below), whose sum is σ = 13452480. Its totient is φ = 9901248.

The previous prime is 11661163. The next prime is 11661197. The reversal of 11661181 is 18116611.

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

It is not a de Polignac number, because 11661181 - 2⁹ = 11660669 is a prime.

It is a super-2 number, since 2×11661181² = 271966284629522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11661101) 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 7 ways as a sum of consecutive naturals, for example, 7036 + ... + 8533.

It is an arithmetic number, because the mean of its divisors is an integer number (1681560).

Almost surely, 2^11661181 is an apocalyptic number.

It is an amenable number.

11661181 is a deficient number, since it is larger than the sum of its proper divisors (1791299).

11661181 is a wasteful number, since it uses less digits than its factorization.

11661181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15683.

The product of its digits is 288, while the sum is 25.

The square root of 11661181 is about 3414.8471415277. The cubic root of 11661181 is about 226.7675173576.

Adding to 11661181 its reverse (18116611), we get a palindrome (29777792).

The spelling of 11661181 in words is "eleven million, six hundred sixty-one thousand, one hundred eighty-one".