11855161 has 4 divisors (see below), whose sum is σ = 11933824. Its totient is φ = 11776500.

The previous prime is 11855159. The next prime is 11855177. The reversal of 11855161 is 16155811.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 16155811 = 7 ⋅2307973.

It is a cyclic number.

It is not a de Polignac number, because 11855161 - 2¹ = 11855159 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11855111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39105 + ... + 39406.

It is an arithmetic number, because the mean of its divisors is an integer number (2983456).

Almost surely, 2^11855161 is an apocalyptic number.

It is an amenable number.

11855161 is a deficient number, since it is larger than the sum of its proper divisors (78663).

11855161 is an equidigital number, since it uses as much as digits as its factorization.

11855161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78662.

The product of its digits is 1200, while the sum is 28.

The square root of 11855161 is about 3443.1324400900. The cubic root of 11855161 is about 228.0180105296.

The spelling of 11855161 in words is "eleven million, eight hundred fifty-five thousand, one hundred sixty-one".