1811806 has 8 divisors (see below), whose sum is σ = 2724624. Its totient is φ = 903600.

The previous prime is 1811791. The next prime is 1811819. The reversal of 1811806 is 6081181.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

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, 106 + ... + 1906.

It is an arithmetic number, because the mean of its divisors is an integer number (340578).

2^1811806 is an apocalyptic number.

1811806 is a deficient number, since it is larger than the sum of its proper divisors (912818).

1811806 is a wasteful number, since it uses less digits than its factorization.

1811806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2306.

The product of its (nonzero) digits is 384, while the sum is 25.

The square root of 1811806 is about 1346.0334319771. The cubic root of 1811806 is about 121.9094104895.

Adding to 1811806 its reverse (6081181), we get a palindrome (7892987).

The spelling of 1811806 in words is "one million, eight hundred eleven thousand, eight hundred six".