221444321 has 8 divisors (see below), whose sum is σ = 259252224. Its totient is φ = 185179680.

The previous prime is 221444317. The next prime is 221444323. The reversal of 221444321 is 123444122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 221444321 - 2² = 221444317 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221444323) 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, 385505 + ... + 386078.

It is an arithmetic number, because the mean of its divisors is an integer number (32406528).

Almost surely, 2^221444321 is an apocalyptic number.

It is an amenable number.

221444321 is a deficient number, since it is larger than the sum of its proper divisors (37807903).

221444321 is an equidigital number, since it uses as much as digits as its factorization.

221444321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 771631.

The product of its digits is 1536, while the sum is 23.

The square root of 221444321 is about 14881.0053759818. The cubic root of 221444321 is about 604.9992678087. Note that the first 3 decimals are identical.

Adding to 221444321 its reverse (123444122), we get a palindrome (344888443).

The spelling of 221444321 in words is "two hundred twenty-one million, four hundred forty-four thousand, three hundred twenty-one".