11331221 has 4 divisors (see below), whose sum is σ = 12361344. Its totient is φ = 10301100.

The previous prime is 11331217. The next prime is 11331227. The reversal of 11331221 is 12213311.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12213311 = 11 ⋅1110301.

It is a cyclic number.

It is not a de Polignac number, because 11331221 - 2² = 11331217 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11331196 and 11331205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11331227) 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, 515045 + ... + 515066.

It is an arithmetic number, because the mean of its divisors is an integer number (3090336).

Almost surely, 2^11331221 is an apocalyptic number.

11331221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11331221 is a deficient number, since it is larger than the sum of its proper divisors (1030123).

11331221 is a wasteful number, since it uses less digits than its factorization.

11331221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1030122.

The product of its digits is 36, while the sum is 14.

The square root of 11331221 is about 3366.1879032520. The cubic root of 11331221 is about 224.6081806256.

Adding to 11331221 its reverse (12213311), we get a palindrome (23544532).

The spelling of 11331221 in words is "eleven million, three hundred thirty-one thousand, two hundred twenty-one".