11811861 has 12 divisors (see below), whose sum is σ = 17092192. Its totient is φ = 7860456.

The previous prime is 11811853. The next prime is 11811869. The reversal of 11811861 is 16811811.

It is an interprime number because it is at equal distance from previous prime (11811853) and next prime (11811869).

It is not a de Polignac number, because 11811861 - 2³ = 11811853 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 (11811869) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7440 + ... + 8886.

Almost surely, 2^11811861 is an apocalyptic number.

It is an amenable number.

11811861 is a deficient number, since it is larger than the sum of its proper divisors (5280331).

11811861 is a wasteful number, since it uses less digits than its factorization.

11811861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2360 (or 2357 counting only the distinct ones).

The product of its digits is 384, while the sum is 27.

The square root of 11811861 is about 3436.8388091384. The cubic root of 11811861 is about 227.7400661915.

The spelling of 11811861 in words is "eleven million, eight hundred eleven thousand, eight hundred sixty-one".