1218805 has 16 divisors (see below), whose sum is σ = 1693440. Its totient is φ = 824832.

The previous prime is 1218787. The next prime is 1218821. The reversal of 1218805 is 5088121.

It is a cyclic number.

It is not a de Polignac number, because 1218805 - 2⁵ = 1218773 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1218805.

It is a congruent number.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 3216 + ... + 3574.

It is an arithmetic number, because the mean of its divisors is an integer number (105840).

2^1218805 is an apocalyptic number.

It is an amenable number.

1218805 is a deficient number, since it is larger than the sum of its proper divisors (474635).

1218805 is an equidigital number, since it uses as much as digits as its factorization.

1218805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 468.

The product of its (nonzero) digits is 640, while the sum is 25.

The square root of 1218805 is about 1103.9950181047. The cubic root of 1218805 is about 106.8180738301.

The spelling of 1218805 in words is "one million, two hundred eighteen thousand, eight hundred five".