221444 has 24 divisors (see below), whose sum is σ = 423360. Its totient is φ = 101024.

The previous prime is 221413. The next prime is 221447. The reversal of 221444 is 444122.

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

It is a plaindrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2627 + ... + 2709.

It is an arithmetic number, because the mean of its divisors is an integer number (17640).

2²²¹⁴⁴⁴ is an apocalyptic number.

It is an amenable number.

221444 is a deficient number, since it is larger than the sum of its proper divisors (201916).

221444 is a wasteful number, since it uses less digits than its factorization.

221444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139 (or 137 counting only the distinct ones).

The product of its digits is 256, while the sum is 17.

The square root of 221444 is about 470.5783675436. The cubic root of 221444 is about 60.4998975478.

Adding to 221444 its reverse (444122), we get a palindrome (665566).

The spelling of 221444 in words is "two hundred twenty-one thousand, four hundred forty-four", and thus it is an iban number.