2218121 has 2 divisors, whose sum is σ = 2218122. Its totient is φ = 2218120.

The previous prime is 2218093. The next prime is 2218127. The reversal of 2218121 is 1218122.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2062096 + 156025 = 1436^2 + 395^2 .

It is a cyclic number.

It is not a de Polignac number, because 2218121 - 2⁶ = 2218057 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2218121.

It is not a weakly prime, because it can be changed into another prime (2218127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1109060 + 1109061.

It is an arithmetic number, because the mean of its divisors is an integer number (1109061).

2^2218121 is an apocalyptic number.

It is an amenable number.

2218121 is a deficient number, since it is larger than the sum of its proper divisors (1).

2218121 is an equidigital number, since it uses as much as digits as its factorization.

2218121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64, while the sum is 17.

The square root of 2218121 is about 1489.3357579807. The cubic root of 2218121 is about 130.4152598913.

Subtracting from 2218121 its reverse (1218122), we obtain a palindrome (999999).

The spelling of 2218121 in words is "two million, two hundred eighteen thousand, one hundred twenty-one".