221324645 has 16 divisors (see below), whose sum is σ = 272187648. Its totient is φ = 172687680.

The previous prime is 221324617. The next prime is 221324659. The reversal of 221324645 is 546423122.

It is not a de Polignac number, because 221324645 - 2¹⁶ = 221259109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 73010 + ... + 75980.

It is an arithmetic number, because the mean of its divisors is an integer number (17011728).

Almost surely, 2^221324645 is an apocalyptic number.

It is an amenable number.

221324645 is a deficient number, since it is larger than the sum of its proper divisors (50863003).

221324645 is a wasteful number, since it uses less digits than its factorization.

221324645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3340.

The product of its digits is 11520, while the sum is 29.

The square root of 221324645 is about 14876.9837332707. The cubic root of 221324645 is about 604.8902608145.

Adding to 221324645 its reverse (546423122), we get a palindrome (767747767).

The spelling of 221324645 in words is "two hundred twenty-one million, three hundred twenty-four thousand, six hundred forty-five".