1218911 has 2 divisors, whose sum is σ = 1218912. Its totient is φ = 1218910.

The previous prime is 1218901. The next prime is 1218913. The reversal of 1218911 is 1198121.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1218911 is a prime.

Together with 1218913, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1218913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 609455 + 609456.

It is an arithmetic number, because the mean of its divisors is an integer number (609456).

2^1218911 is an apocalyptic number.

1218911 is a deficient number, since it is larger than the sum of its proper divisors (1).

1218911 is an equidigital number, since it uses as much as digits as its factorization.

1218911 is an evil number, because the sum of its binary digits is even.

The product of its digits is 144, while the sum is 23.

The square root of 1218911 is about 1104.0430245240. The cubic root of 1218911 is about 106.8211704117.

The spelling of 1218911 in words is "one million, two hundred eighteen thousand, nine hundred eleven".