11805816 has 64 divisors (see below), whose sum is σ = 32503680. Its totient is φ = 3543680.

The previous prime is 11805811. The next prime is 11805817. The reversal of 11805816 is 61850811.

11805816 = T₂₄₃ + T₂₄₄ + ... + T₄₃₉.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11805811) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 51895 + ... + 52121.

It is an arithmetic number, because the mean of its divisors is an integer number (507870).

Almost surely, 2^11805816 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11805816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16251840).

11805816 is an abundant number, since it is smaller than the sum of its proper divisors (20697864).

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

11805816 is a wasteful number, since it uses less digits than its factorization.

11805816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 444 (or 440 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 30.

The square root of 11805816 is about 3435.9592547060. The cubic root of 11805816 is about 227.7012091021.

It can be divided in two parts, 11805 and 816, that added together give a palindrome (12621).

The spelling of 11805816 in words is "eleven million, eight hundred five thousand, eight hundred sixteen".