1801666 has 8 divisors (see below), whose sum is σ = 2728080. Its totient is φ = 892308.

The previous prime is 1801619. The next prime is 1801669. The reversal of 1801666 is 6661081.

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

It is not an unprimeable number, because it can be changed into a prime (1801669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3996 + ... + 4423.

It is an arithmetic number, because the mean of its divisors is an integer number (341010).

2^1801666 is an apocalyptic number.

1801666 is a deficient number, since it is larger than the sum of its proper divisors (926414).

1801666 is a wasteful number, since it uses less digits than its factorization.

1801666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8528.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 1801666 is about 1342.2615244430. The cubic root of 1801666 is about 121.6815577779.

The spelling of 1801666 in words is "one million, eight hundred one thousand, six hundred sixty-six".