2918221 has 4 divisors (see below), whose sum is σ = 2951100. Its totient is φ = 2885344.

The previous prime is 2918213. The next prime is 2918231. The reversal of 2918221 is 1228192.

2918221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 972196 + 1946025 = 986^2 + 1395^2 .

It is a cyclic number.

It is not a de Polignac number, because 2918221 - 2³ = 2918213 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 (2918231) 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 3 ways as a sum of consecutive naturals, for example, 16306 + ... + 16483.

It is an arithmetic number, because the mean of its divisors is an integer number (737775).

2^2918221 is an apocalyptic number.

It is an amenable number.

2918221 is a deficient number, since it is larger than the sum of its proper divisors (32879).

2918221 is an equidigital number, since it uses as much as digits as its factorization.

2918221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32878.

The product of its digits is 576, while the sum is 25.

The square root of 2918221 is about 1708.2801292528. The cubic root of 2918221 is about 142.9023572595.

The spelling of 2918221 in words is "two million, nine hundred eighteen thousand, two hundred twenty-one".