221321005 has 4 divisors (see below), whose sum is σ = 265585212. Its totient is φ = 177056800.

The previous prime is 221321003. The next prime is 221321027. The reversal of 221321005 is 500123122.

221321005 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 130576329 + 90744676 = 11427^2 + 9526^2 .

It is not a de Polignac number, because 221321005 - 2¹ = 221321003 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221321005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221321003) 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, 22132096 + ... + 22132105.

It is an arithmetic number, because the mean of its divisors is an integer number (66396303).

Almost surely, 2^221321005 is an apocalyptic number.

It is an amenable number.

221321005 is a deficient number, since it is larger than the sum of its proper divisors (44264207).

221321005 is an equidigital number, since it uses as much as digits as its factorization.

221321005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44264206.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 221321005 is about 14876.8613961413. The cubic root of 221321005 is about 604.8869447014.

Adding to 221321005 its reverse (500123122), we get a palindrome (721444127).

The spelling of 221321005 in words is "two hundred twenty-one million, three hundred twenty-one thousand, five".