11564221 has 4 divisors (see below), whose sum is σ = 11572444. Its totient is φ = 11556000.

The previous prime is 11564219. The next prime is 11564227. The reversal of 11564221 is 12246511.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 2292196 + 9272025 = 1514^2 + 3045^2 .

It is a cyclic number.

It is not a de Polignac number, because 11564221 - 2¹ = 11564219 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11564192 and 11564201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11564227) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 1410 + ... + 5011.

It is an arithmetic number, because the mean of its divisors is an integer number (2893111).

Almost surely, 2^11564221 is an apocalyptic number.

It is an amenable number.

11564221 is a deficient number, since it is larger than the sum of its proper divisors (8223).

11564221 is an equidigital number, since it uses as much as digits as its factorization.

11564221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8222.

The product of its digits is 480, while the sum is 22.

The square root of 11564221 is about 3400.6206786409. The cubic root of 11564221 is about 226.1372609674.

The spelling of 11564221 in words is "eleven million, five hundred sixty-four thousand, two hundred twenty-one".