2644221 has 4 divisors (see below), whose sum is σ = 3525632. Its totient is φ = 1762812.

The previous prime is 2644219. The next prime is 2644247. The reversal of 2644221 is 1224462.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 2644221 - 2¹ = 2644219 is a prime.

It is a D-number.

It is a Duffinian number.

2644221 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2644261) 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, 440701 + ... + 440706.

It is an arithmetic number, because the mean of its divisors is an integer number (881408).

2^2644221 is an apocalyptic number.

It is an amenable number.

2644221 is a deficient number, since it is larger than the sum of its proper divisors (881411).

2644221 is an equidigital number, since it uses as much as digits as its factorization.

2644221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 881410.

The product of its digits is 768, while the sum is 21.

The square root of 2644221 is about 1626.1060851002. The cubic root of 2644221 is about 138.2820842077.

Adding to 2644221 its reverse (1224462), we get a palindrome (3868683).

The spelling of 2644221 in words is "two million, six hundred forty-four thousand, two hundred twenty-one".