11665566 has 64 divisors (see below), whose sum is σ = 29030400. Its totient is φ = 3441600.

The previous prime is 11665561. The next prime is 11665573. The reversal of 11665566 is 66556611.

It is a zygodrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 11665566.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11665561) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 24115 + ... + 24593.

It is an arithmetic number, because the mean of its divisors is an integer number (453600).

Almost surely, 2^11665566 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11665566, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14515200).

11665566 is an abundant number, since it is smaller than the sum of its proper divisors (17364834).

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

11665566 is a wasteful number, since it uses less digits than its factorization.

11665566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 542 (or 536 counting only the distinct ones).

The product of its digits is 32400, while the sum is 36.

The square root of 11665566 is about 3415.4891304175. The cubic root of 11665566 is about 226.7959378909.

The spelling of 11665566 in words is "eleven million, six hundred sixty-five thousand, five hundred sixty-six".