11681856 has 84 divisors (see below), whose sum is σ = 35483292. Its totient is φ = 3661824.

The previous prime is 11681837. The next prime is 11681869. The reversal of 11681856 is 65818611.

It can be written as a sum of positive squares in 2 ways, for example, as 7617600 + 4064256 = 2760^2 + 2016^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 11681856.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9196 + ... + 10388.

Almost surely, 2^11681856 is an apocalyptic number.

11681856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11681856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17741646).

11681856 is an abundant number, since it is smaller than the sum of its proper divisors (23801436).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

11681856 is a wasteful number, since it uses less digits than its factorization.

11681856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1228 (or 1215 counting only the distinct ones).

The product of its digits is 11520, while the sum is 36.

The square root of 11681856 is about 3417.8730228023. The cubic root of 11681856 is about 226.9014560592.

The spelling of 11681856 in words is "eleven million, six hundred eighty-one thousand, eight hundred fifty-six".