1218111 has 4 divisors (see below), whose sum is σ = 1624152. Its totient is φ = 812072.

The previous prime is 1218089. The next prime is 1218121. The reversal of 1218111 is 1118121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1118121 = 3 ⋅372707.

It is a cyclic number.

It is not a de Polignac number, because 1218111 - 2¹⁵ = 1185343 is a prime.

It is an Ulam number.

It is a D-number.

1218111 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1218121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 203016 + ... + 203021.

It is an arithmetic number, because the mean of its divisors is an integer number (406038).

2^1218111 is an apocalyptic number.

1218111 is a deficient number, since it is larger than the sum of its proper divisors (406041).

1218111 is an equidigital number, since it uses as much as digits as its factorization.

1218111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 406040.

The product of its digits is 16, while the sum is 15.

The square root of 1218111 is about 1103.6806603361. The cubic root of 1218111 is about 106.7977955471.

The spelling of 1218111 in words is "one million, two hundred eighteen thousand, one hundred eleven".