11221555 has 8 divisors (see below), whose sum is σ = 13636800. Its totient is φ = 8863296.

The previous prime is 11221549. The next prime is 11221559. The reversal of 11221555 is 55512211.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 11221555 - 2⁵ = 11221523 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11221559) 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 7 ways as a sum of consecutive naturals, for example, 13810 + ... + 14599.

It is an arithmetic number, because the mean of its divisors is an integer number (1704600).

Almost surely, 2^11221555 is an apocalyptic number.

11221555 is a deficient number, since it is larger than the sum of its proper divisors (2415245).

11221555 is an equidigital number, since it uses as much as digits as its factorization.

11221555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28493.

The product of its digits is 500, while the sum is 22.

The square root of 11221555 is about 3349.8589522546. The cubic root of 11221555 is about 223.8812282230.

Adding to 11221555 its reverse (55512211), we get a palindrome (66733766).

The spelling of 11221555 in words is "eleven million, two hundred twenty-one thousand, five hundred fifty-five".