221335565 has 16 divisors (see below), whose sum is σ = 290920896. Its totient is φ = 160320000.

The previous prime is 221335553. The next prime is 221335571. The reversal of 221335565 is 565533122.

It is not a de Polignac number, because 221335565 - 2¹⁰ = 221334541 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 (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5789 + ... + 21821.

It is an arithmetic number, because the mean of its divisors is an integer number (18182556).

Almost surely, 2^221335565 is an apocalyptic number.

It is an amenable number.

221335565 is a deficient number, since it is larger than the sum of its proper divisors (69585331).

221335565 is a wasteful number, since it uses less digits than its factorization.

221335565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16300.

The product of its digits is 27000, while the sum is 32.

The square root of 221335565 is about 14877.3507386228. The cubic root of 221335565 is about 604.9002089354.

Adding to 221335565 its reverse (565533122), we get a palindrome (786868687).

The spelling of 221335565 in words is "two hundred twenty-one million, three hundred thirty-five thousand, five hundred sixty-five".