1218385 has 12 divisors (see below), whose sum is σ = 1701108. Its totient is φ = 835296.

The previous prime is 1218383. The next prime is 1218391. The reversal of 1218385 is 5838121.

It can be written as a sum of positive squares in 2 ways, for example, as 614656 + 603729 = 784^2 + 777^2 .

It is not a de Polignac number, because 1218385 - 2¹ = 1218383 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1218383) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2242 + ... + 2731.

It is an arithmetic number, because the mean of its divisors is an integer number (141759).

2^1218385 is an apocalyptic number.

It is an amenable number.

1218385 is a deficient number, since it is larger than the sum of its proper divisors (482723).

1218385 is an equidigital number, since it uses as much as digits as its factorization.

1218385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4992 (or 4985 counting only the distinct ones).

The product of its digits is 1920, while the sum is 28.

The square root of 1218385 is about 1103.8047834649. The cubic root of 1218385 is about 106.8058025903.

The spelling of 1218385 in words is "one million, two hundred eighteen thousand, three hundred eighty-five".