1218205 has 8 divisors (see below), whose sum is σ = 1489752. Its totient is φ = 955968.

The previous prime is 1218199. The next prime is 1218209. The reversal of 1218205 is 5028121.

It can be written as a sum of positive squares in 4 ways, for example, as 38809 + 1179396 = 197^2 + 1086^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 1218205 - 2³ = 1218197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1218209) 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 in 7 ways as a sum of consecutive naturals, for example, 2034 + ... + 2563.

It is an arithmetic number, because the mean of its divisors is an integer number (186219).

2^1218205 is an apocalyptic number.

It is an amenable number.

1218205 is a deficient number, since it is larger than the sum of its proper divisors (271547).

1218205 is an equidigital number, since it uses as much as digits as its factorization.

1218205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4655.

The product of its (nonzero) digits is 160, while the sum is 19.

The square root of 1218205 is about 1103.7232442963. The cubic root of 1218205 is about 106.8005426242.

The spelling of 1218205 in words is "one million, two hundred eighteen thousand, two hundred five".