13666641 has 4 divisors (see below), whose sum is σ = 18222192. Its totient is φ = 9111092.

The previous prime is 13666607. The next prime is 13666661. The reversal of 13666641 is 14666631.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 13666641 - 2²¹ = 11569489 is a prime.

It is not an unprimeable number, because it can be changed into a prime (13666661) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2277771 + ... + 2277776.

It is an arithmetic number, because the mean of its divisors is an integer number (4555548).

Almost surely, 2^13666641 is an apocalyptic number.

It is an amenable number.

13666641 is a deficient number, since it is larger than the sum of its proper divisors (4555551).

13666641 is an equidigital number, since it uses as much as digits as its factorization.

13666641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4555550.

The product of its digits is 15552, while the sum is 33.

The square root of 13666641 is about 3696.8420307067. The cubic root of 13666641 is about 239.0858803311.

The spelling of 13666641 in words is "thirteen million, six hundred sixty-six thousand, six hundred forty-one".