2221644 has 12 divisors (see below), whose sum is σ = 5183864. Its totient is φ = 740544.

The previous prime is 2221633. The next prime is 2221657. The reversal of 2221644 is 4461222.

It is a tau number, because it is divible by the number of its divisors (12).

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 2221644.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 92557 + ... + 92580.

2^2221644 is an apocalyptic number.

It is an amenable number.

2221644 is an abundant number, since it is smaller than the sum of its proper divisors (2962220).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2221644 is a wasteful number, since it uses less digits than its factorization.

2221644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185144 (or 185142 counting only the distinct ones).

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

The square root of 2221644 is about 1490.5180307531. The cubic root of 2221644 is about 130.4842687398.

Adding to 2221644 its reverse (4461222), we get a palindrome (6682866).

The spelling of 2221644 in words is "two million, two hundred twenty-one thousand, six hundred forty-four".