12205566 has 40 divisors (see below), whose sum is σ = 27834840. Its totient is φ = 3996432.

The previous prime is 12205561. The next prime is 12205573. The reversal of 12205566 is 66550221.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12205561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 8920 + ... + 10196.

It is an arithmetic number, because the mean of its divisors is an integer number (695871).

Almost surely, 2^12205566 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12205566, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13917420).

12205566 is an abundant number, since it is smaller than the sum of its proper divisors (15629274).

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

12205566 is a wasteful number, since it uses less digits than its factorization.

12205566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1350 (or 1341 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 12205566 is about 3493.6465190400. The cubic root of 12205566 is about 230.2427556634.

Adding to 12205566 its reverse (66550221), we get a palindrome (78755787).

It can be divided in two parts, 1220 and 5566, that added together give a triangular number (6786 = T₁₁₆).

The spelling of 12205566 in words is "twelve million, two hundred five thousand, five hundred sixty-six".