43666 has 8 divisors (see below), whose sum is σ = 74880. Its totient is φ = 18708.

The previous prime is 43661. The next prime is 43669. The reversal of 43666 is 66634.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a nialpdrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 43666.

It is not an unprimeable number, because it can be changed into a prime (43661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1546 + ... + 1573.

It is an arithmetic number, because the mean of its divisors is an integer number (9360).

2⁴³⁶⁶⁶ is an apocalyptic number.

43666 is a deficient number, since it is larger than the sum of its proper divisors (31214).

43666 is a wasteful number, since it uses less digits than its factorization.

43666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3128.

The product of its digits is 2592, while the sum is 25.

The square root of 43666 is about 208.9641117513. The cubic root of 43666 is about 35.2139278561.

The spelling of 43666 in words is "forty-three thousand, six hundred sixty-six".