1806646 has 4 divisors (see below), whose sum is σ = 2709972. Its totient is φ = 903322.

The previous prime is 1806643. The next prime is 1806683. The reversal of 1806646 is 6466081.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1806643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 451660 + ... + 451663.

It is an arithmetic number, because the mean of its divisors is an integer number (677493).

2^1806646 is an apocalyptic number.

1806646 is a deficient number, since it is larger than the sum of its proper divisors (903326).

1806646 is an equidigital number, since it uses as much as digits as its factorization.

1806646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 903325.

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 1806646 is about 1344.1153224333. The cubic root of 1806646 is about 121.7935683073.

The spelling of 1806646 in words is "one million, eight hundred six thousand, six hundred forty-six".