11858221 has 4 divisors (see below), whose sum is σ = 11878812. Its totient is φ = 11837632.

The previous prime is 11858201. The next prime is 11858227. The reversal of 11858221 is 12285811.

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 8934121 + 2924100 = 2989^2 + 1710^2 .

It is a cyclic number.

It is not a de Polignac number, because 11858221 - 2⁹ = 11857709 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 11858221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11858227) 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, 9406 + ... + 10591.

It is an arithmetic number, because the mean of its divisors is an integer number (2969703).

Almost surely, 2^11858221 is an apocalyptic number.

It is an amenable number.

11858221 is a deficient number, since it is larger than the sum of its proper divisors (20591).

11858221 is an equidigital number, since it uses as much as digits as its factorization.

11858221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20590.

The product of its digits is 1280, while the sum is 28.

The square root of 11858221 is about 3443.5767742276. The cubic root of 11858221 is about 228.0376271644.

The spelling of 11858221 in words is "eleven million, eight hundred fifty-eight thousand, two hundred twenty-one".