12166581 has 16 divisors (see below), whose sum is σ = 18589824. Its totient is φ = 6933504.

The previous prime is 12166579. The next prime is 12166589. The reversal of 12166581 is 18566121.

It is not a de Polignac number, because 12166581 - 2¹ = 12166579 is a prime.

It is a super-2 number, since 2×12166581² = 296051386459122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12166589) 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, 11965 + ... + 12941.

It is an arithmetic number, because the mean of its divisors is an integer number (1161864).

Almost surely, 2^12166581 is an apocalyptic number.

It is an amenable number.

12166581 is a deficient number, since it is larger than the sum of its proper divisors (6423243).

12166581 is an equidigital number, since it uses as much as digits as its factorization.

12166581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1580.

The product of its digits is 2880, while the sum is 30.

The square root of 12166581 is about 3488.0626427861. The cubic root of 12166581 is about 229.9973597681.

The spelling of 12166581 in words is "twelve million, one hundred sixty-six thousand, five hundred eighty-one".